Ed Miliband is expected to meet Barack Obama in Washington on Monday as the Labour leader tries to burnish his foreign policy credentials in the run-up to the election.
Mr Miliband was flying to the US capital last night for a short trip which will also see him speak to the Democrat think-tank, the Center for American Progress.
Last week, Mr Miliband’s aides believed they had secured a meeting with the US President, in part thanks to the party’s relationship with the former Obama aide David Axelrod. But there is now nervousness that the meeting could be cancelled due to the problems in Ukraine and Gaza.
Mr Miliband is expected to use the visit to stress that Britain’s position as a full and active member of the EU can only be safeguarded by a Labour government in 2015.