The Arab League has postponed a meeting of foreign ministers in Saudi Arabia to discuss Syria due to take place on Sunday.
King Abdullah of Jordan and the ruling Qatari emir Sheik Hamad had called for “joint Arab action.”
Iran’s president Mahmoud Ahmadinejad had been due to take part in the Jeddah meeting, perhaps severely testing Islamic faultlines over Syria.
Visiting Turkey, US Secretary of State Hillary Clinton said the possibility of imposing no-fly zones in Syria was being studied - the closest she has come to suggesting direct military intervention.
However, nothing would be decided without “intense analysis and operational planning”, she said.
Western countries like Britain and now Canada, whose foreign minister was in Jordan, have announced help for Syrian rebels fighting the regime – but not weapons.
“We made a decision not to provide certainly any lethal support although we are prepared to help in non lethal support, whether it is how to promote democracy and freedom, how to build a pluralist society,” the Canadian Foreign Minister John Baird told a news conference.
Canada’s aid for Syria will be worth 2.8 million euros. Meanwhile a consignment of French medical supplies and equipment for Syrian refugees has arrived at the Zaatari camp in Jordan.