Tony Blair has denied he is becoming an electoral "liability" to the Labour Party over his support for US policy in Iraq.
Tony Blair says the US and UK must finish the job in Iraq
The prime minister dismissed speculation about his leadership as "froth and bubble".
"When you do something like Iraq you've got to see it through," Mr Blair told BBC Radio Newcastle.
He dismissed calls to distance himself from President George Bush amid concern about abuse of Iraqis by US forces.
Mr Blair, who is visiting the North East, attempted to switch focus back to the domestic agenda.
In an interview with BBC Radio Newcastle, he said the vast bulk of his time is spent on domestic issues and pointed to the UK's economic success and investment in public services.
Mr Blair is reportedly facing pressure from senior figures in his party to spell out an independent policy on the Middle East and Iraq.
But in an interview in the Independent, he said he would not end British support for its "main ally" at such a time.
He also dismissed calls to stand down before the general election.
Foreign Secretary Jack Straw, speaking in Washington, underlined the message of unity by praising US and British forces in rebuilding the country.
He said the UK "utterly condemned" the mistreatment of Iraqi prisoners.
But he added: "We will continue to remind the world that it's thanks to our armed forces that Iraq is on the path to being a sovereign and democratic state, and we will achieve it together."
In his interview, Mr Blair admitted he was "frustrated" that difficulties in Iraq had distracted attention from the government's domestic achievements on the economy, jobs and public services.
The prime minister told the Independent: "I know we are going through a difficult time. People should just take a step back and look at the fundamentals.
"Despite the appalling stuff about prisoner abuse, we are trying with the majority of the Iraqi people to get the country on its feet.
"We have just got to make sure we prevail and succeed. It is in the interests of the world that we do. The alternative is not one we should contemplate."
It was "in the interests of the world" that the US/UK military coalition remained in Iraq, said Mr Blair.
And he dismissed reports he was thinking about letting Chancellor Gordon Brown take over as prime minister as "froth".
He said: "I think I should get on with the
job. I enjoy doing it."
Ex-defence minister Lewis Moonie confirmed there was talk on the government backbenches about "things not going very well" and speculation that Labour "might get a hammering" in next month's European and local elections.
"It would be a lie for me to suggest that people are not talking about whether he is likely to carry on or
not," he told BBC Radio 4's Today programme.
"There's a lot of general talk but not to the extent that people are saying the prime minister ought to go," he told BBC Radio 4's Today programme.
Meanwhile another backbencher, who did not want to be named, said the Labour Party would only tolerate Tony Blair while he remained a winner.
"He's more dependent on being a winner than other leaders because he's not ideologically wedded to Labour like, say, John Smith was," the MP told BBC News Online.
He said the Labour benches were split between those who believed the UK could only resolve the Iraq situation with the US and those who wanted the government to distance itself from George Bush's Republican administration.
But the MP warned against paying too much attention to speculation that supporters of Chancellor Gordon Brown were mounting a bid to get their man into the top job on the back of discontent over Iraq.
"Brown has always been as much an Atlanticist as Blair."
Bookmakers have also been reporting an increase in punters expecting to see Mr Blair stepping down - with the odds on his quitting office being cut from 8-1 to 5-2.
"We've taken more money for Blair to go than for UK to win this weekend's Eurovision Song Contest," said William Hill spokesman Graham Sharpe.
"We have had people coming in wanting to bet up to £2,000 a time that he'll be out of office before the next general election."