Tony Blair has endorsed Ian Murray to be the next deputy leader of the Labour Party.

The former prime minister said the Edinburgh South MP “gets it” and understood that Labour could not return to “being a protest movement”.

Murray, who is Labour’s only MP in Scotland, has also been backed by former prime minister Gordon Brown and former chancellor Alistair Darling.

In a statement released on Tuesday, Blair said the party faced a “huge challenge” having “lost four times in a row”

“Ian Murray understands that if Labour is to have any hope, it’s got to be able to win in every part and every corner of the United Kingdom,” he said.

Blair used a speech last week to warn the party it would be the “end” if it did not stop its left-wing membership from pushing what he called “unrealistic” policies.

Murray has been a harsh critic of Jeremy Corbyn’s leadership of the party and has pinned the blame for the 2019 election defeat on the outgoing leader.

He said today the party needs “to put a Scot in the leadership team” in order to win.

“I’m proud to have the endorsement of both of Labour’s living prime ministers,” he said.

“Without winning back Scotland, they could be the last Labour prime ministers.”

Murray is up against frontrunner Angela Rayner as well as Richard Burgon, Dawn Butler and Rosena Allin-Khan in the contest to replace Tom Watson.

Rayner, who is seen as running away with the contest, last night issued a rare criticism of Corbyn’s leadership.

“I would expect more discipline in a way that Jeremy didn’t,” she told ITV News.

“He didn’t command respect, and he therefore wasn’t able to command that collectivism in the Labour Party.”

Voting in the race to succeed Corbyn as leader opened on Monday, with party members set to choose between Keir Starmer, Rebecca Long-Bailey and Lisa Nandy.