Gordon Brown says he is determined to continue with the job
Gordon Brown has described last week's call by two former cabinet colleagues for him to face a secret leadership ballot as a "form of silliness".
In an interview with The News Of The World, he also says he will serve a full term if Labour is re-elected.
But ex-Labour Party general secretary Peter Watt told the Mail on Sunday they were unlikely to win under Mr Brown.
Geoff Hoon, who had called for a leadership ballot, has said it appears not to have succeeded and is "over".
Former defence secretary Mr Hoon and former health secretary Patricia Hewitt wrote to all Labour MPs on Wednesday calling for a ballot on Mr Brown's leadership, saying the party was "deeply divided" and it was hindering Labour's chances of getting its message across during the general election campaign.
But only a handful of backbenchers publicly backed it and Mr Hoon said on Friday he accepted they did not "appear to have succeeded" but he did not regret doing it.
However there has been continued speculation about Mr Brown's level of support among senior cabinet colleagues, some of whom took hours to publicly oppose the call for a ballot.
In an interview with the News of the World on Sunday, Mr Brown said he was getting on with the job, adding: "I am the prime minister and am determined to remain so. I am determined, I am resolute."
"I can't answer for the feelings of one or two people. But politics is full of... you know, large numbers of people are involved and they make their own decisions," he said.
"They have got to be free to make the choices they want. I'm sorry it happened. I think it was a form of silliness."
Mr Brown also said he had been "drawing on" the advice of his predecessor, Tony Blair, adding: "Tony and I talk a lot."
Foreign Secretary David Miliband, often touted as a future Labour leader, took more than six hours to respond to the call for a leadership ballot on Wednesday. But he told the BBC: "I am absolutely committed to ensure we get the strongest possible Labour vote at the next general election under Gordon's leadership."
And the Chief Secretary to the Treasury, Liam Byrne, said it was not significant that cabinet ministers had taken some time to respond.
"We are pretty focussed on the day job, actually, so we didn't want to give this the kind of seriousness that some people in the media thought it should be given," he told the BBC.
"They weren't rushing into TV studios because we knew the widespread feeling in the Parliamentary Labour Party was that this had no backing and no support."
He said he believed there was unanimous agreement in cabinet that Mr Brown could lead Labour to an election victory.
But Conservative leader David Cameron, in an interview with BBC One's Andrew Marr Show on Sunday, said the coup attempt showed that Labour was too divided to rule.
He said his party was "ready at any time" for a general election.
He went on: "If anything, the last week demonstrates that we need to have strong determined leadership from a united government, we can't get that from Labour and Gordon Brown and an increasing number of people in the Labour Party even seem to be saying that.
"When you contemplate the problems we have in our country .. there's never been a time when we've more needed strong decisive leadership from a united team."
Former Labour general secretary Mr Watt told the Mail on Sunday: "Gordon is a big political figure but he lacks the emotional intelligence required by a modern leader. If you cannot connect with people you will fail. Leaders like Tony Blair and Margaret Thatcher were fantastic communicators. Gordon just doesn't have those skills."
In his memoirs he said Downing Street was a "shambles" after Mr Brown took over and said that the prime minister had spent £1.2m on the "election that never was" in 2007.
Mr Watt resigned as the party's administrative chief in 2007 after admitting he knew businessman David Abrahams had been donating cash to Labour through third parties.
Mr Byrne dismissed the Mail story as "a bit of innuendo and gossip" which related to events that took place some years ago. He added that Mr Watt was "a thoroughly decent guy but the chap's got a book to sell".