The Labour MP for Hartlepool, where Reform UK took all 12 seats up for grabs, has called for Sir Keir Starmer to go.
Jonathan Brash, whose wife Pamela Hargreaves, leader of Hartlepool council, lost her seat as the council slipped into no overall control, said the Prime Minister should “set out a timetable for his departure” on Friday.
Mr Brash, who has previously said he did not expect Sir Keir to lead the party into the next general election, told The Guardian: “It has been a terrible night for the Labour Party.
“What I’ve seen here is extraordinarily good, hard-working, Hartlepool people lose their seats.
“I’ve seen canvassers working night and day in this election and it’s all been for naught and the reason has absolutely nothing to do with them.”
He added: “They are delivering for this town, they have been delivering for this town and the reality is we need change at the top of the Labour Party.
“I think the very best thing the Prime Minister could do now is address the nation tomorrow and set out a timetable for his departure.
“We can then have an orderly transition, one that, by the way, ensures the full breadth of talent within the Labour Party is able to stand, should it want to.”
Mr Brash also said it was “time to stop the political cowardice” on big issues affecting the country.