ANKARA/BEIRUT (Reuters) – The United States is considering a no-fly zone in Syria as it weighs options for intervention into the 2-year-old civil war, Western diplomats said on Friday, after the White House said Syria had crossed a “red line” by using nerve gas.

After months of deliberation, President Barack Obama’s administration said on Thursday it would now arm rebels, having obtained proof the Syrian government used chemical weapons against fighters trying to overthrow President Bashar al-Assad.

WASHINGTON/BEIRUT (Reuters) – 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 that 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.

WASHINGTON/BEIRUT (Reuters) – The United States has concluded that Syrian President Bashar al-Assad’s forces used chemical weapons against rebel fighters and Washington will supply direct military assistance to the opposition, the White House said on Thursday.

The new assessment and 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.

BEIRUT (Reuters) – U.S. President Barack Obama is deciding whether to take new action to help Syria’s rebels, the White House said on Thursday, while President Bashar al-Assad’s surging forces and their Lebanese Hezbollah allies turned their guns on the north.

Assad’s forces fought near the northern city of Aleppo on Thursday and bombarded the central city of Homs, having seized the initiative by winning the open backing of Hezbollah last month and capturing the strategic town of Qusair last week.

BEIRUT/PARIS (Reuters) – Western officials will meet the commander of the main force fighting President Bashar al-Assad on Saturday to discuss new aid, diplomats said, signaling a new bid to help mainstream rebels and counter the strength of sectarian militias.

Underscoring the West’s fears of an uncontrolled sectarian bloodbath, activists said Sunni insurgent militiamen had killed some 60 Shi’ites in a town in the east of Syria.

BEIRUT (Reuters) – Sunni Muslim insurgents have killed about 60 Shi’ite Muslims in a rebel-held eastern Syrian town where President Bashar al-Assad’s agents had been trying to recruit and arm fighters for his cause, according to opposition sources on Wednesday.

The attack was another sign of how a revolt that began more than two years ago with peaceful protests against four decades of Assad family rule is descending into sectarian bloodshed.

BEIRUT (Reuters) – The United Nations warned on Friday that half of all Syrians will need humanitarian aid by the end of 2013 and launched what it said was the largest emergency appeal in history to cope with the civil war crisis.

“Syria as a civilization is unraveling,” said the U.N. High Commissioner for Refugees, Antonio Guterres, announcing the call for some $5 billion before the end of the year.

BEIRUT (Reuters) – The Syrian army seized control on Wednesday of the strategic border town of Qusair, Syrian media and security sources said, in a major advance for President Bashar al-Assad’s forces in the country’s two-year civil war.

Rebels said they had pulled out of Qusair, which lies on a cross-border supply route with neighbouring Lebanon and where they had fought fierce battles with government forces and Hezbollah guerrillas for more than two weeks.

BEIRUT/GENEVA (Reuters) – As Syrian government forces try to grind down rebel resistance in the besieged town of Qusair, trapped civilians have had to choose between sheltering from the bombs or risking a 100 km hike to safety.

“Qusair itself is described as a ghost town, heavily damaged and filled with the sound of bombs. People are hiding in bunkers or, even worse, in holes that they’ve dug. One woman told us that she spent, with her children, one week inside a hole that was dug into the ground,” UNHCR chief spokeswoman Melissa Fleming told a U.N. briefing in Geneva.

BEIRUT (Reuters) – Syrian President Bashar al-Assad said on Thursday Moscow was still committed to sending him advanced anti-aircraft weapons, although a source close to the Russian defense ministry said the missiles had yet to arrive.

The prospect of the missiles arriving is a serious worry for Western and regional countries opposing Assad which have called on Moscow not to send them.