Labour has suspended MP Naz Shah over comments she made about Israel.
The Bradford West MP has been heavily criticised over the Facebook posts, including one suggesting Israel should be moved to the United States.
In a Commons statement she offered a "profound apology" for the posts, which were made before she became an MP.
Earlier party leader Jeremy Corbyn warned her about the "offensive and unacceptable" posts and David Cameron called for her suspension.
Labour said: "Jeremy Corbyn and Naz Shah have mutually agreed that she is administratively suspended from the Labour Party by the general secretary.
"Pending investigation, she is unable to take part in any party activity and the whip is removed."
Apologising in the Commons, Ms Shah, who had already quit as an unpaid aide to shadow chancellor John McDonnell, said: "Anti-Semitism is racism, full stop. As an MP I will do everything in my power to build relationships between Muslims, Jews and people of different faiths and none."
The announcement of her suspension came after pressure mounted on the MP, with Mr Cameron saying during Prime Minister's Questions it was "quite extraordinary" that Labour had not withdrawn the whip from her over what he suggested were "racist" comments.
Analysis by Iain Watson, BBC political correspondent
Saying sorry three times didn't prevent Naz Shah's suspension.
Number 10 are taking credit - but one shadow cabinet member, Lisa Nandy, had already called for her suspension and I'm told other Labour figures had approached party officials privately to call for the same thing.
Ten days ago Labour's general secretary had reassured MPs those accused of anti-Semitism would be expelled or suspended.
Insiders say that once the Labour leader had decided to hand the matter to party officials, suspension - and an investigation - became inevitable.
Most Labour MPs recognise few members hold anti-Semitic views but that some high-profile cases have been toxic, and have been pressing their leadership to be more proactive in uncovering and rooting out unacceptable views.
And some on the party's right are keen to force a leader who has opposed "witch hunts" of party members to use disciplinary procedures to erect, however reluctantly, some walls to Labour's broad church - and to make clear that the views of some recent members and supporters aren't welcome.
Minutes before PMQs, Mr Corbyn issued a statement, saying: "These are historic social media posts made before she was a member of parliament. Naz has issued a fulsome apology.
"She does not hold these views and accepts she was completely wrong to have made these posts. The Labour Party is implacably opposed to anti-Semitism and all forms of racism."
Labour MP Lisa Nandy had called for Ms Shah's suspension, while another Labour MP, Kate Hoey, told BBC Radio 4's The World at One she should resign "right away" from the Commons Home Affairs Committee, which is carrying out an inquiry into anti-Semitism.
Who is Naz Shah?
Sabbiyah Pervez, BBC Look North
Naz Shah burst onto the political scene during the 2015 general election, where she ousted Respect MP George Galloway.
Her selection as a candidate proved controversial with divisions emerging in the local party. The candidate who was chosen first stood down four days later, before Ms Shah was imposed by the ruling National Executive Committee.
A bitter campaign followed, with Mr Galloway sparking anger by questioning Ms Shah's account of her forced marriage.
After her victory, she was celebrated locally and nationally for her unique background and life experiences.
Growing up in poverty in Bradford, Ms Shah and her family were abandoned by her father who eloped with a neighbour's teenage daughter. She has spoken openly about her experience of surviving a forced marriage and domestic violence.
In a Facebook post in 2014, Ms Shah shared a graphic showing an image of Israel's outline superimposed on a map of the US under the headline "Solution for Israel-Palestine conflict - relocate Israel into United States", with the comment "problem solved".
The post suggested the US has "plenty of land" to accommodate Israel as a 51st state, allowing Palestinians to "get their life and their land back".
It added Israeli people would be welcome and safe in the US, while the "transportation cost" would be less than three years' worth of Washington's support for Israeli defence spending.
Ms Shah added a note suggesting the plan might "save them some pocket money".
The post was brought to light by the Guido Fawkes website, which also highlighted a post in which she appeared to liken Israeli policies to those of Hitler.
In a statement, the MP said: "I made these posts at the height of the Gaza conflict in 2014, when emotions were running high around the Middle East conflict.
"But that is no excuse for the offence I have given, for which I unreservedly apologise."
She set out a more detailed apology in an article for Jewish News.
"The language I used was wrong," she wrote.
"It is hurtful. What's important is the impact these posts have had on other people. I understand that referring to Israel and Hitler as I did is deeply offensive to Jewish people for which I apologise."
The Board of Deputies of British Jews said the comments were "simply appalling", calling for an urgent meeting "for clarification of her views on Israel and the UK Jewish community".