U.S. Secretary of State Hillary Clinton said Tuesday that the world needs to decide how to end the conflict in Syria and start planning for a political transition in Damascus.

"We must figure out how to hasten the day when bloodshed ends and the political transition begins," she said after talks with her South African counterpart Maite Nkoana-Mashabane.

Lebanon has informed Iran that it will not take part in an upcoming meeting on the Syrian conflict that Tehran is hosting, a Lebanese diplomatic official said on Tuesday.

"The Lebanese foreign ministry has informed the Iranian authorities that Lebanon will not attend Thursday's meeting in Tehran, because it has never participated in any international meetings on Syria, in line with its policy of self-disassociation," the official told Agence France Presse on condition of anonymity.

More than 22,000 Iraqis have fled the violence in Syria for their home country in less than three weeks, joining over 12,000 Syrian refugees, a U.N. refugee agency official said on Tuesday.

"Since the 18th of July until yesterday (Monday), 22,300 Iraqi refugees have been registered" after having arrived from Syria, UNHCR Iraq representative Claire Bourgeois told a news conference in Baghdad.

Tehran will continue to back Syria under President Bashar Assad, which acts as a pillar of an Iranian-led regional alliance, top envoy Saeed Jalili told Assad in Damascus on Tuesday.

"Iran will never allow the resistance axis -- of which Syria is an essential pillar -- to break," said Jalili, a top aide to Iranian supreme leader Ayatollah Ali Khamenei.

Syrians are in urgent need of life-saving medicines following an escalation in fighting, which also threatens further food shortages, U.N. agencies warned on Tuesday.

"The recent escalation of clashes has resulted in substantial damage to the pharmaceutical plants located in rural Aleppo, Homs and rural Damascus," said World Health Organization (WHO) spokesman Tarik Jasarevic.

An Alawite film director was assassinated near his home on the outskirts of Damascus, Syria's General Cinema Institute said on Tuesday.

"Treacherous hands assassinated" Bassam Mohieddin on Sunday, the institute said in a statement, adding the killing took place in Jdaidet Artuz, scene of recent clashes between troops and rebels.

Bahrain's government on Tuesday distanced itself from Islamist MPs who visited Syria at the weekend and delivered aid to rebels in the north where they are fighting regime forces.

"The entry into Syria by a number of Bahraini MPs took place without notifying the foreign ministry," the ministry said in a statement carried by BNA official news agency.

The Iranian Chief of General Staff Hasan Fruzabadi held Turkey, Saudi Arabia and Qatar responsible for bloodshed in Syria in a statement published on the Revolutionary Guard’s website.

“To help the war plans of the Great Satan (USA) is not a good principal to follow for neighboring countries. If they are acting on this basis, then they should know that the next time, it will be Turkey’s and other countries turn to take the fall,” Fruzabadi said.

Iranian Foreign Minister Ali Akbar Salehi will pay a snap visit to Turkey late Tuesday for talks on the Syrian crisis and 48 Iranians kidnapped there, officials said.

The Iranian foreign minister wanted to visit Turkey "at his own request," which was conveyed through diplomatic channels late Monday, a Turkish diplomat told AFP, speaking on condition of anonymity.

Some 1,137 Syrians, including a defecting general, have fled to Turkey amid the escalating violence in the strife-torn Syria, the Anatolia news agency reported Tuesday.

The latest group brought the number of Syrian refugees in Turkey to nearly 50,000.