Western and Gulf nations opposed to Syrian President Bashar al-Assad will hold their latest meeting in London on May 15 to discuss stepping up support for rebels, Britain's Foreign Office said Tuesday.
The core 11 countries involved in the so-called "Friends of Syria" will also seek ways of getting aid into Syria, and discuss the political situation ahead of a widely criticised presidential election in June, it said.
British Foreign Secretary William Hague will host the talks, which US Secretary of State John Kerry is expected to attend.
"This meeting comes at a time of widespread indiscriminate regime violence against civilians, plans to hold elections which will be a grotesque parody of democracy, and the regime's complete failure to provide humanitarian access," it said.
"Foreign Ministers will discuss how best to significantly step up our support to the Syrian opposition, make urgent progress on improving the deteriorating humanitarian crisis and reinvigorate a political process that has stalled due to regime intransigence."
The 11 nations include Western powers the United States, Britain, France, Germany and Italy as well as key regional opponents of Assad: Qatar, Saudi Arabia, Turkey and the United Arab Emirates.
Arab powers Egypt and Jordan are also part of the group, which does not include Assad's allies Russia and Iran.