One of Keir Starmer’s closest cabinet allies has vowed to step up his support for the embattled prime minister.

Lord Hermer said the PM’s working class background will help him deliver for voters and see off “populists” on the left and right of British politics.

The attorney general’s comments, in a speech on Tuesday night, will come just hours after Starmer made a plea for cabinet unity following days of bitter Labour in-fighting.

The prime minister was even forced to insist he will still be Labour leader come the next general election amid mounting speculation about his future.

Hermer will tell the Law for Change group that things like the Hillsborough Law, the Employment Rights Bill and improved rights for renters prove Starmer is on the side of ordinary people.

He will say: “When the law helps extend rights and delivers justice where it’s most needed, it earns not just respect, but belief.

“Not as a shield for the status quo, particularly when that status quo may fail too many. But as a promise that across the country, we all stand equal before the law, and no one stands alone.”

Hermer will add: “That’s what this prime minister believes in – the idea that power can be rebalanced, that the law can and should evolve to meet the changing needs of society.

“Injustices can be addressed, wrongs can be made right, through graft, patience and, above all, determination. That’s the story of the man I know, Keir Starmer.

“Populists to the left and right say you don’t need any of that. Just ban this thing, leave this convention. All will be well. But who is left to pick up the pieces, when it all goes south? Working class people. Like the family Keir Starmer grew up in.”

A source close to Hermer told HuffPost UK he wanted to help Starmer see off the twin threats of both Reform UK and the Tories.

He said: “He will be ramping up his efforts in the coming months in support of the rule of law as a platform for change, and of the prime minister.

“Populists falsely claim there are some easy, magical solutions to his country’s challenges, but the attorney general and the prime minister both completely understand you need proper solutions to give rights to working class people and tackle inequality.

“He will be making the case that because of Keir’s working class background, he gets the challenges this country faces.

“But the PM also understands the risks – Reform’s false solutions wouldn’t harm Nigel Farage and his friends, but working class people in this country.”

Starmer’s government was rocked last week by a briefing war which saw No.10 sources accuse health secretary Wes Streeting of plotting to replace him.

But that backfired on Downing Street, with Streeting emerging stronger from the row and the PM facing calls to sack Morgan McSweeney, his chief of staff.

In an attempt to draw a line under the controversy, Starmer told the weekly cabinet meeting on Tuesday morning that the government must get back to “working as a team”.

His spokesman said: “He said distractions meant our focus shifted from where it mattered most – working every day in the service of the British people

“People were rightly impatient for change and we have to deliver that rather than talking about ourselves. That means working as a team offering opportunity and security and delivering on our mandate.”

In an interview with the Daily Mirror published this morning, Starmer insisted he will still be Labour leader at the next election despite a poll suggesting only a third of his own voters want him to.

Asked directly if he will still be PM when the country next goes to the polls, he said: “Yes, I will. Let me be really clear – every minute that’s not spent talking about and dealing with the cost of living is a minute wasted of the political work of this government.

“That’s my response to last week. I remain utterly focused on what matters to me most, which is bearing down on the cost of living and making people feel better off.”