There are growing concerns that Syria's sectarian-tinged civil war could spread beyond its borders. Mr. Assad's regime is largely backed by the heterodox Alawite sect he belongs to, and is largely opposed by Syria's Sunni Arab majority. There has been scattered fighting between Alawites and Sunnis in Lebanese city of Tripoli recently, and some fear the regional implications are growing.
Smuggled guns are filtering into Syria but it is not clear if Arab or other governments are backing any such transfers. Iraqi security officials say there are signs Sunni Muslim insurgents are beginning to cross the border to join Syrian rebels. Smugglers are cashing in as prices double for weapons reaching Syria concealed in commercial traffic.
For now, however, such weaponry cannot match the firepower that Assad's military can bring to bear, analysts say, but that could change if Assad fails to heed Arab peace calls. A non-Gulf Arab ambassador said Qatar and Saudi Arabia had insisted on the "material support" wording to cover "all kinds of support including weapons in future", adding: "But we see this as a dangerous escalation."
A senior Arab diplomat voiced fears that such a step could ignite a conflagration in Syria, a nation of Sunnis, Alawites, Christians, Kurds and Druze at the heart of the Arab world.
Syria was a major supplier of Sunni jihaddis to the insurgency against the US occupation of Iraq, and there are signs that the Sunni Iraqis are now reciprocating. Sunni Islamists have long been repressed by Assad's regime, and the smuggling lines that kept arms and men flowing to battles in Iraq's Anbar province can run the other way.