Labour’s deputy leader Tom Watson has announced he will be stepping down as an MP.
Mr Watson, who had represented West Bromwich East since 2001, said in a letter to party leader Jeremy Corbyn that “serving the Labour Party has been the privilege of a lifetime.”
Mr Watson, 52, joined Labour in 1982 and was elected as the party’s deputy leader in 2015.
The father-of-two said it had been an “immense honour to represent people from Sandwell” and that “the Black Country is the very best of Britain”.
He continued: “But now is the right time for me to stand down from the House of Commons and start a different kind of life. The decision is personal, not political.”
Referencing his pronounced differences with Mr Corbyn, Mr Watson said: “The disagreements we have had inside the party are well-known; now is not the time to rehearse them again.”
Mr Watson, who is regarded as a party moderate, has had a number of public spats with Labour’s left-wing.
In September, the Labour Party’s ruling body considered abolishing the post of deputy leader. Mr Watson said he was only made aware when he got a text as he sat in a restaurant in Manchester on the previous evening.
Mr Watson has been publicly critical of the leadership’s attempts to tackle anti-Semitism in the party, saying reform and action was too slow.
He also pushed for the party to support a second EU referendum and defied Mr Corbyn by calling for the party to back a new public vote before the country went to the polls in December.
Mr Corbyn thanked his colleague for his contribution to the party after the shock resignation.
In a response to Mr Watson, the Labour leader said: “Few people have given as much to the Labour movement as you have and I know that many thousands of members and trade unionists that you have inspired and worked with over the years will be very sorry to see you go.”
He continued: “Although you are stepping down, I know we will continue to work together on the issues you have always championed and which we share a passion for: taking on the vested interests of the Murdoch empire, the sugar industry and the gambling companies, and standing up for the rights and interests of the people of this country.”
On a personal note, Mr Corbyn added: “I’ve always enjoyed our very convivial chats about many things, including cycling, exercise and horticulture. I hope the horseradish plants I gave you thrive.”
In addition to tensions within the party, Mr Watson has also faced harsh criticism after he promoted the false claims of a Westminster paedophile ring made by fantasist Carl Beech.
Mr Watson has previously commented: “I have always said that it wasn’t my place to judge whether sexual abuse allegations were true or false – that was for the police.”
Harvey Proctor, who was one of those who was falsely accused, said Mr Watson “has done his constituents a great favour” by stepping down.
Mr Watson said in his departure statement he intends to continue to work in politics.
He said: “I might be leaving Westminster but I won’t be leaving politics altogether.
“I will continue to champion progressive social democracy and a political culture that is inclusive, diverse and respects the opinions of others. In recent years we’ve lost sight of that simple politeness which used to define us as a nation.
“We need to find it again.”
For Mr Watson’s next move, he said he wanted to “devote the next phase of my life to public health, using my own experience and working with entrepreneurs and public servants.”
His plans include setting up a ‘remission for all’ movement for those impacted by type 2 diabetes, an illness that Mr Watson battled previously himself before he lost seven stone in weight.
Mr Watson will continue as deputy leader until the day voters head to the polls on 12 December.
He held his West Bromwich East seat with a 7,713 majority at the previous election.
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