Labour’s Tristram Hunt is to stand down as MP for Stoke-on-Trent Central to become the director of the V&A museum in London.
The former shadow education secretary said he had “no desire to rock the boat” and insisted anyone who interpreted his decision to quit that way is “just plain wrong”.
But Mr Hunt said he had become frustrated over how Labour should respond to the shockwaves to have hit mainstream politics.
In a letter to local party members, he wrote: “As I enter a new role as a public servant, I will be leaving partisan politics behind me and will work impartially as a museum director.
“I am sorry to put you, the party and the people of Stoke-on-Trent through a by-election.
“I have no desire to rock the boat now and anyone who interprets my decision to leave in that way is just plain wrong.”
Mr Hunt is the second centrist Labour MP in a matter of weeks to quit Parliament for a job outside politics, following Jamie Reed, who announced last month he was standing down as MP for Copeland to take up a post at the Sellafield nuclear plant.
Their decisions to quit politics are being seen by Westminster-watchers as a sign of Labour’s remaining Blairites losing hope of reversing the party’s shift to the left.
Mr Hunt’s departure sets up another potentially awkward by-election for Mr Corbyn, in a traditionally safe Labour seat where Ukip made a strong showing in the last general election. Stoke voted Leave by 65.7% in last year’s EU referendum - one of the biggest Brexit votes in the country.
Labour has held Stoke-on-Trent Central since the constituency’s creation in 1950, with a vote-share of 66% and majority of 49.5%, making it one of the party’s safest strongholds in 1997.
But its majority has since fallen to 17%, with Ukip surging by 18 points to take second place in 2015, and the febrile state of UK politics means Labour cannot be as confident of holding onto the seat as it has been in the past.
There was immediate speculation that Ukip’s new leader Paul Nuttall may stand in the by-election in a bid to make good on his promise to replace Labour as the party of choice for working class communities in the Midlands and North of England.
Former Ukip leader Nigel Farage said: “Tristram Hunt’s resignation from Stoke will be followed by many others. Labour is doomed.”