"We have a problem and we need to move quickly," Labour MP Catherine West has said as she defended her efforts to trigger a leadership challenge against the prime minister.

The north London MP has said she would prefer to see a Cabinet member put themselves forward to replace Sir Keir Starmer but that she would consider doing so herself if they did not act.

Speaking to the BBC's Laura Kuenssberg, West said she would listen to Sir Keir's planned relaunch speech on Monday but would mount a challenge if she remained "dissatisfied".

Addressing the MP directly on the same programme, Education Secretary Bridget Phillipson said: "I love you dearly Catherine, but we just disagree on this one".

The senior minister acknowledged her party had taken "a real kicking" from voters in Thursday's elections but said it was not a sign Labour should "spend time talking amongst ourselves, arguing amongst ourselves, fighting amongst ourselves".

"We do need to tell a better story, we do need to deliver faster," she said.

The party lost almost 1,500 councillors in England, mainly to Reform UK and the Greens, and was kicked out of power in Wales. Labour came joint second in Scotland, where the SNP retained control of the Parliament.

West, a former junior minister, is not bidding to be the next Labour leader and prime minister herself, but by triggering a leadership contest she would be aiming to flush out heavyweight contenders she thinks could do a better job than Sir Keir.

In order to trigger a leadership contest, 20% of Labour MPs - 81 people - would have to back her. She has said she currently has 10 MPs who would be prepared to endorse her.

More than 30 Labour MPs have publicly called for the prime minister to resign or to set out a timetable for his departure.

West told the BBC: "I will hear what the prime minister's got to say tomorrow and, then if I'm still dissatisfied, I will put out my email to the Parliamentary Labour Party, asking for names.

"And the reason I'm doing that is not for me. It's for working people, because Labour is the only party that can beat Reform."

Asked if she could gather enough names to start a contest, the Hornsey and Friern Barnet MP said: "We will find out when I put out my email to the Parliamentary Labour Party.

"But what we need is that timetable from the chair of the party [Anna Turley], and she and I are very good friends, she knows, I've asked her for an orderly transition into a leadership election."

Reflecting on the election results, Phillipson said people did not feel the Labour government had "delivered" on the change it promised in the 2024 general election.

The Cabinet minister warned that the rise of Reform UK - which made huge gains in the elections - was a "perilous moment" for the country, and that only Labour could "bring our quite divided country back together".

Sir Keir will try to reset his premiership in a major speech on Monday and that will be followed by the King's Speech, in which the government will set out the new laws it intends to pass in the coming year.

Phillipson said the prime minister would use the speech on Monday to set out a "fresh direction for our country and for our party".

Asked if Sir Keir would still be party leader at the time of the next general election, which will come in 2029 at the latest, Phillipson said: "Yes, I do believe that."

But Sharon Graham, leader of the Unite union, said she was "very sure" that the prime minister would not lead Labour into the next election.

Nadine Dorries, a former Conservative minister who switched to Reform, said Sir Keir was an "asset" to her new party.

"We'd love Starmer to stay there" she said but added: "For the sake of the country... Labour should change their leader."

Health Secretary Wes Streeting, former deputy prime minister Angela Rayner and Greater Manchester Mayor Andy Burnham are thought to be the main potential challengers to Sir Keir's leadership.

Burnham cannot enter a contest without first becoming an MP and earlier this year, he was blocked by the party's ruling body from standing in the Gorton and Denton by-election.

The mayor's supporters are hoping a leadership contest can be delayed until he is able to return to Parliament.

On Sunday, Josh Simons and Anna Dixon became the latest Labour MPs to urge the prime minister to step down.

Simons was a senior figure in Labour Together - the organisation that helped Sir Keir win the Labour leadership - and was until last month a minister.

Writing in The Times, he said: "I do not believe the prime minister can rise to this moment. He has lost the country. He should take control of the situation by overseeing an orderly transition to a new prime minister."

Dixon, MP for Shipley, told BBC Politics North: "I don't believe that the public any longer have confidence that the prime minister can take us successfully into the next set of elections".

She said she thought the prime minister was a "good man" but needed to "take control of this... and plan for an orderly transition in our leadership".

Liberal Democrat leader Sir Ed Davey said: "The prime minister has refused to see the results of this week's local elections for what they are: A referendum on him and his failure to tackle the cost-of-living crisis.

He argued that building a closer relationship with the EU was "the best way to deliver the economic growth that this country desperately needs" but that Sir Keir's plans were "too weak and unambitious".

He urged potential Labour leadership candidates to "commit to fixing our broken relationship with Europe".

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