America's new Secretary of State John Kerry will hold talks with the Prime Minister and Foreign Secretary William Hague on the first stop in an 11-day world tour.
The conflict in Syria, nuclear stand-off with Iran and Middle East peace process are expected to be high on the agenda.
But the Falklands is also likely to come up - with Washington under pressure to recognise the result of a referendum next month on whether the islanders want to remain British.
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ITV News' team of political correspondents sum up the final, frantic push for votes in the general election before the polls open tomorrow.
Rain continues across Scotland and parts of northern England tonight, drier overnight and cool for everyone
A summary of the day's election campaign stories in under one minute.