The Prime Minister will meet with Barack Obama today to discuss trade liberalisation, development and Syria during his three-day visit to America.
The two leaders will be joined in the Oval Office by US secretary of state John Kerry, Mr Cameron's national security adviser Kim Darroch, and opposite number Tom Donilon.
David Cameron will urge a peace conference on Syria by the end of the month, believing that efforts to end the 27 month conflict have gained some momentum after his trip to Sochi for talks with President Vladimir Putin last week, and Mr Kerry's visit to Moscow.
One of the main obstacles to easing the situation has been Russian support for Bashar Assad's regime.
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