"As Tony Blair said, we stand shoulder-to-shoulder with the American people and with President Bush," he added at a news conference following the talks. 
Candidates meeting
Brown's visit has been overshadowed by
the Pope's six-day US tour [EPA]
Blair was viewed as a close ally of the Bush administration, particularly over the Iraq war, and his popularity in the UK suffered as a result.
Brown, in the US for a three-day visit, also met the three major candidates vying to succeed Democrats Hillary Clinton and Barack Obama as well as Republican John McCain.
However he said he did not favour any specific candidate.
"It is for Americans to decide who their president is going to be, he said."
Despite the talks with Bush, the UK prime minister's visit has been overshadowed by Pope Benedict XVI's simultaenous six-day tour of the US.
Iran condemned
Both leaders also condemned Iran for its ongoing nuclear programme, with Bush saying that those who thought Iran's programme had no military intent were "naive".
"Our position is clear: That we're going to work together along with other nations to make it abundantly clear to the Iranian regime that they must not have the capability of developing a nuclear weapon," said Bush.
"Gordon Brown seriously sees the threat, as do I. And now is the time to confront the threat. And I believe we can solve the problem diplomatically," he added.
Brown also said he would continue to press other European leaders for an extension of European sanctions against Iran.
Western powers accuse Iran of enriching uranium in order to develop weapons however Iran says its programme is purely for civilian purposes.