While many have congratulated Sir Keir Starmer on his win, some are criticising the party for still failing to elect a female leader.
Professor Rohan McWilliam, who leads the Labour History Research Unit at Anglia Ruskin University, says the party has "yet again... proved a masculine party in which women cannot get the top job" - in contrast with the Tories who have had two women prime ministers.
He claims Sir Keir has "yet to show that he is an inspirational leader" and that his "ambiguity has served him well".
More on shadow cabinet...
Our political editor says that during the campaign, Sir Keir Starmer promised jobs for the others in the leadership race in his shadow cabinet.
She adds: "It sounds like he will favour the rising generation for big jobs, rather than bringing back people who have already had ministerial experience into big roles, but let's see.
"The rumour mill is turning already."
Shadow cabinet appointments expected tomorrow
Now Sir Keir Starmer is in charge of the Labour Party, the next step is to appoint his new top team.
BBC political editor Laura Kuenssberg says we can expect the first appointments to come tomorrow...
Watch: What does Starmer win mean for Labour Party?
Video content
Video caption: The BBC’s chief political correspondent on the Labour leadership election result and what could happen under new leader Sir Keir Starmer.The BBC’s chief political correspondent on the Labour leadership election result and what could happen under new leader Sir Keir Starmer.
Vicki Young said there was “great uncertainly” about his polices
over renationalisation, and who he will choose for his shadow cabinet would
“give a clue about the direction” he will take the party.
But she added the coronavirus virus outbreak had "changed
the political landscape".
Drakeford: New leader will 'stand up for Wales'
BBCCopyright: BBC
The leader of Labour in Wales has welcomed Sir Keir Starmer to his new post.
Mark Drakeford says his colleague has become leader "at a critical time for our country", and his leadership in Parliament "will be crucial in the coming months" to tackle coronavirus.
But, for him, he was also sure Sir Keir would "stand up for Wales' interests and support the work of the Welsh Labour government in delivering for the people of Wales".
Labour's new deputy leader, Angela Rayner, thanks everyone "from the bottom of [her] heart" for their support.
On Twitter, she promises to do "everything to repay your trust".
She adds: "I know we face a long and difficult road ahead, but it’s our responsibility to offer the better future that the citizens of our country deserve."
Jewish Labour Movement says election must 'mark a turning point'
PA MediaCopyright: PA Media
The National Chair of the Jewish Labour Movement calls for the election of the new leadership team to "mark a turning point" for the Labour Party when it comes to the row over anti-Semitism.
Mike Katz says "nobody should be under any illusion", as restoring trust with the community will "take effort, time and political will".
He adds: "We need to see strong, moral leadership on the vital task of ridding the Labour Party of anti-Semitism from the outset and changing a toxic culture that tolerates racism."
Mr Katz says his organisation will "work constructively with the new leadership team" and they were "encouraged" by pledges from both Sir Keir Starmer and Angela Rayner.
But he adds: “The past five years have without doubt been one of the darkest times for Jewish Labour members and supporters.
"We will dare to be optimistic that the party can once again be a safe place for Jews, but we are equally clear that this is just the beginning of that process.”
Former Labour leaders welcome Starmer to ranks
It is not just Jeremy Corbyn who has congratulated Sir Keir Starmer on his election.
Labour's previous three leaders have taken to Twitter to welcome him to the club.
Sir Keir Starmer may have been in the job for less than two hours, but he has already been onto the phone to the prime minister to talk about the coronavirus outbreak.
A spokesman for the new Labour leader says he accepted an earlier offer from Boris Johnson to meet next week to discuss the outbreak, as well as agreeing arrangements on the Privy Council - a formal body of advisers to the Queen, which the leader of the opposition is entitled to join.
The spokesman adds: "Keir offered to work constructively with the government on how best to respond to the coronavirus outbreak."
Corbyn pledges to work with Starmer and Rayner
Outgoing Labour leader Jeremy Corbyn has congratulated Sir Keir Starmer and Angela Rayner on their election victories.
Writing on Twitter, he says: "Being Labour Party leader is a great honour and responsibility.
"I look forward to working with Keir and Angela to elect the next Labour government and transform our country."
Who is Angela Rayner?
PA MediaCopyright: PA Media
Angela Rayner has been elected Labour’s new deputy leader.
She has been a long-standing member of Jeremy Corbyn’s cabinet, but will now hold one of the key jobs in the party.
Opposition parties pledge to work with new Labour leader during crisis
Getty Images/PA MediaCopyright: Getty Images/PA Media
Ian Blackford and Sir Ed Davey have both congratulated the new Labour leaderImage caption: Ian Blackford and Sir Ed Davey have both congratulated the new Labour leader
The other opposition parties in Westminster have offered their congratulations to Sir Keir Starmer on his election as Labour leader.
The SNP's Westminster leader, Ian Blackford, says it is "vital opposition parties work together effectively to hold the UK government to account - and ensure people get the support they need in the coronavirus crisis".
He appeals to Sir Keir to support SNP pledges on financial support during the outbreak and its calls to pause trade negotiations with the EU. And he adds a warning: "Support for Labour has collapsed in Scotland. If they are ever to regain trust, they must stop ignoring Scotland's wishes and respect our democratic right to choose our own future."
The Liberal Democrats' acting leader, Sir Ed Davey, also pledges to work with Sir Keir to hold the government to account over its response to coronavirus.
He says his party will always work with others when it comes to "pursuing our liberal values".
He adds: "As the chapter closes on one Labour leader, we hope the new one can see the Labour party play a constructive role in building an effective multi-party opposition. That will be the litmus test of Keir Starmer’s leadership."
Which voters opted for Keir Starmer?
As we reported earlier, Sir Keir Starmer won the Labour leadership contest on first preference votes - but who voted for him?
The electorate was made up of party members, supporters of affiliated organisations and registered supporters who paid £25 to take part.
Sir Keir's support was strongest among the registered supporters, where he hoovered up a massive 78% of the vote.
His next best result came among party members themselves, where he got 56% of the votes.
His weakest base of support came among members of affiliated groups - where he won a more slender majority of 53% of votes cast.
Analysis: Starmer has a massive task ahead
Laura Kuenssberg
BBC political editor
Whatever your own politics, this is a really big moment.
Labour could now be an opposition that gets things done and carries out effective scrutiny - Labour under Corbyn struggled ever to do that.
Keir Starmer has a massive task to get the party to start working in that way again, and make it function in a way that's anything like normal.
He's said he has a "mountain to climb," but you could argue it's like crossing the Himalayas without oxygen.
But the party is huge, and Jeremy Corbyn created a massive membership base.
At December's election, many expressed no particular affection for the Conservatives but were unimpressed with Labour on Brexit, and simply couldn't imagine Mr Corbyn on the steps of Downing Street.
Nothing is inevitable about the 2024 election. But Keir Starmer's first steps in these first few weeks will matter enormously.
Live Reporting
Jennifer Scott and Paul Seddon
All times stated are UK
That's all folks
We are bringing our live page coverage to a close for today.
If you want to read more of our coverage on the Labour leadership contest, here are some highlights below:
Thanks for joining us and enjoy your weekend.
Labour proved as 'masculine party yet again'
While many have congratulated Sir Keir Starmer on his win, some are criticising the party for still failing to elect a female leader.
Professor Rohan McWilliam, who leads the Labour History Research Unit at Anglia Ruskin University, says the party has "yet again... proved a masculine party in which women cannot get the top job" - in contrast with the Tories who have had two women prime ministers.
He claims Sir Keir has "yet to show that he is an inspirational leader" and that his "ambiguity has served him well".
More on shadow cabinet...
Our political editor says that during the campaign, Sir Keir Starmer promised jobs for the others in the leadership race in his shadow cabinet.
She adds: "It sounds like he will favour the rising generation for big jobs, rather than bringing back people who have already had ministerial experience into big roles, but let's see.
"The rumour mill is turning already."
Shadow cabinet appointments expected tomorrow
Now Sir Keir Starmer is in charge of the Labour Party, the next step is to appoint his new top team.
BBC political editor Laura Kuenssberg says we can expect the first appointments to come tomorrow...
Victory for Starmer supporters on ruling body
Away from the main contests, there will also be changes today to the make-up of the National Executive Committee, Labour’s ruling body.
Sir Keir's supporters have won effective control of the body following victories in a series of separate elections.
BBC political editor Laura Kuenssberg reports that Sir Keir's team are delighted with the results, which they didn't expect at the start.
She adds that trying to run the party without control of the NEC is hard, as Jeremy Corbyn team found out before they won control in 2017 polls.
Former leadership contender welcomes Starmer win
Owen Smith tried to become Labour leader in 2016 after MPs had a vote of no confidence in Jeremy Corbyn.
But the membership ensured Mr Corbyn remain in the top job.
He has now tweeted his congratulations to Sir Keir Starmer.
Watch: What does Starmer win mean for Labour Party?
Video content
Vicki Young said there was “great uncertainly” about his polices over renationalisation, and who he will choose for his shadow cabinet would “give a clue about the direction” he will take the party.
But she added the coronavirus virus outbreak had "changed the political landscape".
Drakeford: New leader will 'stand up for Wales'
The leader of Labour in Wales has welcomed Sir Keir Starmer to his new post.
Mark Drakeford says his colleague has become leader "at a critical time for our country", and his leadership in Parliament "will be crucial in the coming months" to tackle coronavirus.
But, for him, he was also sure Sir Keir would "stand up for Wales' interests and support the work of the Welsh Labour government in delivering for the people of Wales".
You can read more from the Welsh Labour leader here.
Corbyn ally steps down from Labour frontbench
Former shadow home secretary tweets
One of Jeremy Corbyn's staunchest allies, and his neighbour in north London, tweets that she's stepping down from her post as shadow home secretary...
Five challenges facing new Labour leader
Sir Keir Starmer has just become Labour leader - but what is likely to be at the top of his in-tray?
Even before the coronavirus emergency, Jeremy Corbyn's successor was facing a formidable set of challenges.
Read here about five challenges facing Labour's new leader.
Rayner promises to 'repay trust' of supporters
Labour's new deputy leader, Angela Rayner, thanks everyone "from the bottom of [her] heart" for their support.
On Twitter, she promises to do "everything to repay your trust".
She adds: "I know we face a long and difficult road ahead, but it’s our responsibility to offer the better future that the citizens of our country deserve."
Jewish Labour Movement says election must 'mark a turning point'
The National Chair of the Jewish Labour Movement calls for the election of the new leadership team to "mark a turning point" for the Labour Party when it comes to the row over anti-Semitism.
Mike Katz says "nobody should be under any illusion", as restoring trust with the community will "take effort, time and political will".
He adds: "We need to see strong, moral leadership on the vital task of ridding the Labour Party of anti-Semitism from the outset and changing a toxic culture that tolerates racism."
Mr Katz says his organisation will "work constructively with the new leadership team" and they were "encouraged" by pledges from both Sir Keir Starmer and Angela Rayner.
But he adds: “The past five years have without doubt been one of the darkest times for Jewish Labour members and supporters.
"We will dare to be optimistic that the party can once again be a safe place for Jews, but we are equally clear that this is just the beginning of that process.”
Former Labour leaders welcome Starmer to ranks
It is not just Jeremy Corbyn who has congratulated Sir Keir Starmer on his election.
Labour's previous three leaders have taken to Twitter to welcome him to the club.
Johnson congratulates new Labour leader
Prime Minister Boris Johnson has also joined the congratulations to Sir Keir Starmer on his election as Labour leader.
He confirms the pair will meet next week at a briefing on coronavirus.
Starmer speaks to PM on coronavirus
Sir Keir Starmer may have been in the job for less than two hours, but he has already been onto the phone to the prime minister to talk about the coronavirus outbreak.
A spokesman for the new Labour leader says he accepted an earlier offer from Boris Johnson to meet next week to discuss the outbreak, as well as agreeing arrangements on the Privy Council - a formal body of advisers to the Queen, which the leader of the opposition is entitled to join.
The spokesman adds: "Keir offered to work constructively with the government on how best to respond to the coronavirus outbreak."
Corbyn pledges to work with Starmer and Rayner
Outgoing Labour leader Jeremy Corbyn has congratulated Sir Keir Starmer and Angela Rayner on their election victories.
Writing on Twitter, he says: "Being Labour Party leader is a great honour and responsibility.
"I look forward to working with Keir and Angela to elect the next Labour government and transform our country."
Who is Angela Rayner?
Angela Rayner has been elected Labour’s new deputy leader.
She has been a long-standing member of Jeremy Corbyn’s cabinet, but will now hold one of the key jobs in the party.
So how did she get to this point?
You can read our full profile here.
Opposition parties pledge to work with new Labour leader during crisis
The other opposition parties in Westminster have offered their congratulations to Sir Keir Starmer on his election as Labour leader.
The SNP's Westminster leader, Ian Blackford, says it is "vital opposition parties work together effectively to hold the UK government to account - and ensure people get the support they need in the coronavirus crisis".
He appeals to Sir Keir to support SNP pledges on financial support during the outbreak and its calls to pause trade negotiations with the EU. And he adds a warning: "Support for Labour has collapsed in Scotland. If they are ever to regain trust, they must stop ignoring Scotland's wishes and respect our democratic right to choose our own future."
The Liberal Democrats' acting leader, Sir Ed Davey, also pledges to work with Sir Keir to hold the government to account over its response to coronavirus.
He says his party will always work with others when it comes to "pursuing our liberal values".
He adds: "As the chapter closes on one Labour leader, we hope the new one can see the Labour party play a constructive role in building an effective multi-party opposition. That will be the litmus test of Keir Starmer’s leadership."
Which voters opted for Keir Starmer?
As we reported earlier, Sir Keir Starmer won the Labour leadership contest on first preference votes - but who voted for him?
The electorate was made up of party members, supporters of affiliated organisations and registered supporters who paid £25 to take part.
Sir Keir's support was strongest among the registered supporters, where he hoovered up a massive 78% of the vote.
His next best result came among party members themselves, where he got 56% of the votes.
His weakest base of support came among members of affiliated groups - where he won a more slender majority of 53% of votes cast.
Analysis: Starmer has a massive task ahead
Laura Kuenssberg
BBC political editor
Whatever your own politics, this is a really big moment.
Labour could now be an opposition that gets things done and carries out effective scrutiny - Labour under Corbyn struggled ever to do that.
Keir Starmer has a massive task to get the party to start working in that way again, and make it function in a way that's anything like normal.
He's said he has a "mountain to climb," but you could argue it's like crossing the Himalayas without oxygen.
But the party is huge, and Jeremy Corbyn created a massive membership base.
At December's election, many expressed no particular affection for the Conservatives but were unimpressed with Labour on Brexit, and simply couldn't imagine Mr Corbyn on the steps of Downing Street.
Nothing is inevitable about the 2024 election. But Keir Starmer's first steps in these first few weeks will matter enormously.