Gordon Brown will meet the US president, George Bush, for their first formal face-to-face summit at the weekend.
The prime minister will see Mr Bush at the presidential retreat of Camp David in Maryland on Sunday night, before heading to New York to give an address to the United Nations.
Mr Brown has already met Mr Bush informally in Washington while he was waiting to take over from Tony Blair, but this is the first time the two men will have met since he assumed power.
According to the White House, the two men will focus on "continuing to move forward on issues of shared interests and concerns" - principally Iraq and Afghanistan.
Mr Brown arrives at Camp David on Sunday night for dinner and talks, followed by further talks on Monday morning before travelling to New York on Monday afternoon, where he will meet the UN general secretary, Ban Ki-Moon.
Though Downing Street and the foreign secretary, David Miliband, have stressed there will be no change in the special relationship between the two countries, there has been speculation that there will be a different tone.
Two weeks ago one of Mr Brown's most trusted proteges, the trade and development secretary, Douglas Alexander, made a speech in Washington pointedly calling for the US to "recognise the importance of a rules-based international system".
"We need to demonstrate by our deeds, words and our actions that we are internationalist, not isolationist, multilateralist, not unilateralist, active and not passive, and driven by core values, consistently applied, not special interests," he said.
In addition, Mr Brown has appointed the former deputy UN general secretary and Iraq war-sceptic, Mark Malloch Brown to his foreign affairs team.
Lord Malloch-Brown has described himself as "proud to be an anti-neo con" and said that the US and UK should be allied but not "joined at the hip".
Mr Brown himself opted to travel first to see Nicolas Sarkozy in Paris and Angela Merkel in Berlin before heading to Washington.
Downing Street does not normally announce the PM's movements so far in advance, but was pre-empted by an announcement from Tony Snow, Mr Bush's spokesman.