Arab states of the Gulf on Monday urged the UN Security Council to hold an emergency meeting to prevent a "massacre" in Syria's central city of Homs, the target of a fierce offensive by regime troops.
In a statement, the six Gulf Cooperation Council (GCC) members announced they are "following with deep concern... the unjust siege Syrian regime forces are imposing on Homs... with military support from the militias of the (Shiite) Lebanese Hezbollah movement and under the umbrella of Iran's Revolutionary Guards".
Rebel-held districts of Homs have been the target of a new army offensive since Saturday.
The six Gulf monarchies -- Bahrain, Kuwait, Oman, Qatar, the United Arab Emirates and Saudi Arabia -- urged the "Security Council to urgently meet to break the siege on Homs and prevent the Syrian regime and its allies from committing horrific massacres".
Dubbed the "capital of the revolution" by activists, Homs is important because it is on the road linking Damascus to the coast and its central location is also key as a supply route.
The third largest city in Syria was one of the first to join the uprising against President Bashar al-Assad's regime more than two years ago.
Saudi Arabia, meanwhile, reiterated its call for a UN resolution "banning the supply of arms to the Syrian regime which has lost all it legitimacy".
It urged the international community to "protect the Syrian people and help them defend themselves against the heinous crimes carried out" by Assad's regime "with help of foreign forces".
In a statement after the weekly cabinet meeting chaired by Crown Prince Salman bin Abdul Aziz, the government urged the European Union to "immediately implement" its decision to lift an embargo on weapons destined for Syrian rebels.
More than 100,000 are estimated to have been killed in the Syrian conflict so far, which flared when Assad loyalists launched a bloody crackdown on pro-reform protests in March 2011.