President Barack Obama has authorized sending U.S. weapons to Syrian rebels for the first time, a U.S. official said on Thursday after the White House said it has proof the Syrian government had used chemical weapons against opposition forces fighting to overthrow President Bashar al-Assad.
The U.S. decision came as Assad's surging forces and their Lebanese Hezbollah allies turned their guns on the north, fighting near the northern city of Aleppo and bombarding the central city of Homs after having seized the initiative by winning the open backing of Hezbollah last month and capturing the strategic town of Qusair last week.
The White House said Washington would provide "direct military support" to the opposition but did not specify whether it would include lethal aid, which would mark a reversal of Obama's resistance to arming the rebels. But the U.S. official, speaking on condition of anonymity, said the package would include weapons.
Syrian rebel and political opposition leaders immediately called for anti-aircraft and other sophisticated weaponry.
The arrival of thousands of seasoned, Iran-backed Hezbollah Shi'ite fighters to help Assad combat the mainly Sunni rebellion has shifted momentum in the two-year-old war, which the United Nations said on Thursday had killed at least 93,000 people.
U.S. and European officials anxious about the rapid change are meeting the commander of the main rebel fighting force, the Free Syrian Army, on Friday in Turkey. FSA chief Salim Idriss is expected to plead urgently for more help.
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Obama has been more cautious than Britain and France, which forced the European Union this month to lift an embargo that had blocked weapons for the rebels.
After months of investigation, the White House on Thursday laid out its conclusions that chemical weapons were used by Assad's forces, but it stopped short of threatening specific actions in response to what Obama said would be a "game changer" for Washington's handling of the conflict.
"The president ... has made it clear that the use of chemical weapons or transfer of chemical weapons to terrorist groups is a red line," said Ben Rhodes, Obama's deputy national security adviser. "He has said that the use of chemical weapons would change his calculus, and it has."