Keir Starmer has been warned by his predecessor as Labour leader, Jeremy Corbyn, that a shadow cabinet reshuffle will not be enough to restore the party’s hopes after its drubbing at the polls this week.

The warning came as the Labour leader struggled to reassert control over the party with a shake-up of his top team which dragged on late into the evening as senior figures apparently resisted moves to new jobs.

After deputy leader Angela Rayner’s dramatic removal as party chair and campaign co-ordinator in the wake of the loss of Hartlepool, there were increasingly mutinous noises from the Labour left, with one former member of Corbyn’s shadow cabinet saying a challenge to the leadership could not be ruled out.

And Greater Manchester mayor Andy Burnham – tipped as a future leader after offering one of Labour’s few points of light in a torrid set of election results – went public with his dismay at Rayner’s demotion, tweeting: “I can’t support this.”

Starmer loyalist Ian Murray insisted that Ms Rayner has not been sacked, as she was being offered a more high-profile role in the leadership team. But after Labour officials confirmed a reshuffle was planned on Sunday, there was speculation that the planned revamp was being blocked by her reluctance to accept the move.

With no official denial that the positions of shadow chancellor Anneliese Dodds, shadow foreign secretary Lisa Nandy, shadow home secretary Nick Thomas-Symonds and chief whip Nick Brown were in question, one insider described the situation as a “mess”.

Meanwhile, there was no public comment from Starmer as Labour activists celebrated victories in mayoral contests in London, Greater Manchester, Liverpool, Salford, Bristol, Cambridgeshire, West Yorkshire and the West of England.

Sir Keir was faced with a potentially difficult by-election within weeks of the traumatic Hartlepool defeat, as Tracy Brabin confirmed she will step down as MP for Batley and Spen after her election as West Yorkshire metro mayor. Her 3,525 majority in the 2019 general election was smaller than the 3,595 margin comprehensively overturned by Tories in the north-east seaside town.

Writing in The Independent, Mr Corbyn accused his successor of failing to inspire supporters to turn out to vote and urged him to “learn the lessons from this disaster” and set out a vision based on policies from the last two Labour manifestos.

“People turn out to vote when they are inspired,” said Corbyn, who is currently suspended from the parliamentary Labour Party. “With millions simply not turning up to vote in these elections, even in the context of the pandemic these results show a loss of hope.” The former leader warned: “It is new ideas from across our movement – not reshuffles or cosmetic tweaks – that will bring hope back.”

Mr Corbyn said there was a consensus across Labour for a programme based on a living wage, rights at work, safe and secure housing, transport, broadband and energy, properly funded healthcare and education and “an economy that puts the planet before profit, and the needs of the many before the greed of the few”.

And he pointedly added: “They are the programme Keir Starmer was elected on. They are not mine or anyone else’s, but the product of a movement of 600,000 party members and trade unions representing millions of workers, and a programme that inspired hundreds of thousands to organise in their communities and persuade people around them, during and beyond election time.”

Corbyn’s 2017 campaign co-ordinator Jon Trickett said that local constituency parties are already preparing motions of no confidence in Sir Keir’s leadership, amid accusations that he has failed to keep promises from his leadership campaign to continue with a raft of policies drawn up under Corbyn.

Mr Trickett told left-wing commentator Owen Jones in an online discussion: “If it comes to the question ought there to be a leadership challenge, I don’t think we should rule it out.

“I don’t think we should rule it out for several reasons, but perhaps the most important is that a leader who won the vote on the back of promises that were reneged on – some of them quite quickly – needs to come clean.”

And Richard Burgon, who served Corbyn as shadow justice secretary, said: “It’s clear that the Labour leadership’s current approach is not working. 

“There should now be a special Labour Party conference where the leadership outlines its plan to turn this around and seeks the confidence of the party for it.”

But former Labour leader Neil Kinnock said Starmer should not be blamed for the debacle.

“From 2019 and before, and particularly in the year of Covid, we’ve lacked definition,” Lord Kinnock told The Independent. “Given the long-running trends and the pandemic, little of the deficiency is on Keir Starmer’s account. 

“In this age of insecurity, we must manifestly be the party of personal, family, community and national security. That must apply across all policy areas and with deliberate focus and promotion.

“It is directly relevant to the needs of British people everywhere, consistent with Labour values and purposes and therefore authentic, and Keir exudes the intelligence and steadiness which embodies security.”