Secretary of State John Kerry announced Washington will double its aid to the Syrian opposition with an additional $123 million, bringing the total US commitment to some $250 million.
At a meeting in Istanbul of 10 European and Middle Eastern countries, Kerry made clear that the fresh aid would expand support to the rebels, who already receive food and medical kits, to "include other types of non-lethal supplies."
The assistance will go to an umbrella group, the National Coalition of Syrian Revolutionary and Opposition Forces, which has been fighting President Bashar al-Assad's forces during the two-year civil war.
In return, the Syrian coalition committed to enter negotiation talks aimed at hammering out a political transition once Assad has left. They also pledged to protect minorities and that the new government would be democratic.
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“This conflict is now spilling across borders and is now threatening neighboring countries,” Kerry said at a joint news conference with Turkey's foreign minister and Syrian coalition leader Moaz al-Khatib. “The president directed me to step up our efforts.”
Syrian government daily Al-Watan accused the US of having "thrown oil on the fire" of the Syrian conflict.
The so-called "Friends of Syria" nations, however, did not meet the opposition's request for arms, a no-fly zone along the country's northern and southern borders, or direct intervention.
The opposition had demanded the allies carry out air strikes against pro-Assad forces, to stop them from launching Scud missiles.
At the meeting, Kerry asked the leaders of the other nations to contribute additional funds, with the objective of raising a total of $1 billion in international aid.
Over the past two years, more than 70,000 people have been killed in Syria's bloody conflict.