Sir Gerald Kaufman, Labour MP for Manchester Gorton and Father of the House of Commons, has died aged 86.
His family made the announcement late on Sunday, calling him "a great socialist and parliamentarian".
Sir Gerald, who was the oldest serving MP, famously called his party's left-wing 1983 election manifesto "the longest suicide note in history".
Labour Party leader Jeremy Corbyn led tributes to him, calling him an "iconic and irascible figure".
Former Labour Prime Minister Gordon Brown said: "There was no one quite like Gerald Kaufman: a brilliant speaker, a compelling writer, an acerbic wit and a conscientious constituency MP.
"With his sharp insights, he not only penned many famous lines but gave the wisest of advice to Labour leaders who relied upon him throughout his 47 years in Westminster."
Tony Blair, Labour prime minister from 1997 to 2007, said: "Gerald was an extraordinary man, passionate, principled, acerbic and absolutely dedicated to the cause of social justice and the Labour Party."
A family spokesman confirmed he had been suffering from a long-term illness.
Prime Minister Theresa May said she had been "very sad" to learn of Sir Gerald's death.
"His was a life of remarkable commitment to his constituents in Manchester and to the political life of the nation... as Father of the House (a title taken by the longest serving MP) his wisdom and experience will be very much missed by MPs on all sides of the House."
Sir Gerald became an MP in north-west England in 1970, first for the Manchester Ardwick constituency and then for Manchester Gorton, which he had served since 1983.
He was a junior minister between 1974 and 1979, and held a number of senior shadow cabinet posts through the 1980s, before returning to the backbenches in the early 1990s.
A family spokesman said: "Sir Gerald dedicated his life to serving those who he believed would benefit most from a Labour government and Labour values in action.
"He believed that policy and principle without power were simply not enough to deliver the better life that he fought for on behalf of his constituents for almost 50 years.
"[Throughout his illness], he remained firmly committed to, and focused on, the activities and wellbeing of his beloved constituency."
By BBC obituary editor Nick Serpell
Gerald Kaufman rose from a working-class background to become one of the longest-serving MPs of his generation.
He gained a reputation as a persistent, often waspish, interrogator whose withering putdowns became a feature of his time in Parliament.
A practising Jew, he was best known for his fierce opposition to the policies of the Israeli government and its treatment of the Palestinians.
Possessed of a sardonic wit, he was a prolific writer and columnist who also wrote satirical sketches for the BBC, an organisation that he later frequently criticised.
Sir Gerald was a member of the Jewish Labour Movement and was known for his criticism of Israel, calling senior politicians from the country "war criminals" in 2002.
Mr Corbyn said: "Gerald came from a proud Jewish background. He always wanted to bring peace to the Middle East and it was my pleasure to travel with him to many countries.
"He loved life and politics. I will deeply miss him, both for his political commitment and constant friendship."
Former leader Ed Miliband said he was "an outstanding servant of the Labour movement", adding: "His principles, values and friendship will be sorely missed."
Tributes from across the political spectrum have been paid to Sir Gerald.
Shadow Chancellor John McDonnell tweeted: "Sad to hear of Gerald Kaufman's death. He was a tremendously dedicated servant of his constituency and our party. A man of absolute principle."
Commons Speaker John Bercow called him an "outstanding representative" and a "passionate campaigner for social justice, here in Britain and around the world".
Former Labour shadow minister Chuka Umunna tweeted: "Very sad to hear of Sir Gerald's death. A true Labour man and one of the most eloquent parliamentarians. Thoughts are with his family."
Conservative MP Michelle Donelan MP said: "So sad to hear that Sir Gerald Kaufman MP for Manchester Gorton and Father of The House of Commons, has passed away."
And Tory MP Peter Heaton-Jones tweeted: "Sad to hear that Sir Gerald Kaufman, Father of the House of Commons, has died. Extraordinary public service: 47 years an MP."