World leaders are gathering in Northern Ireland for a G8 summit set to be dominated by the conflict in Syria.
UK Prime Minister David Cameron said he hoped the G8 nations would focus on "common ground" on the issue of bringing peace to Syria.
But Russia, Syria's key ally, opposes US plans to arm the rebels—something leader Vladimir Putin made clear after talks with Mr Cameron on Sunday.
The two-day summit is also expected to focus on global economic issues.
Mr Cameron, the host, hopes to oversee the launch of talks for an EU-US free trade deal and achieve progress on tax transparency.
Other nations joining the UK, US and Russia for the 39th Summit of the Group of Eight (G8) in Lough Erne, County Fermanagh, are Canada, France, Germany, Italy and Japan.