Pope Benedict XVI has called on the Syrian leadership to respond urgently to the "legitimate" demands of its people who have been facing an increasingly bloody crackdown by President Bashar Assad's regime.

Benedict called for all sides, but especially Syria's political leaders, to enter into talks to end the uprising.

The head of a controversial Arab League observer mission to Syria has resigned, an Arab League official told Agence France Presse on Sunday.

The resignation of General Mohammed Ahmed Mustafa al-Dabi was due to be officially announced at a meeting of Arab foreign ministers in Cairo later in the day, the official said, without saying why the Sudanese former military intelligence officer had quit.

Shelling by the Syrian army killed at least 14 civilians in the central protest city of Homs on Sunday, a rights group said.

The Britain-based group said all but one of them died in Baba Amr, a rebel stronghold in the city which armed forces have targeted for more than a week, killing at least 500 people, according to activists.

A Syrian kidnapped in the Bekaa town of Taanayel was set free at dawn Sunday for the purpose of providing the abductees with a ransom in return for the release of his two brothers and their employee, the National News Agency reported.

The four men - brothers Osama, Imad and Hisham Abdul Raouf and their employee Khaled al-Hamadeh - were kidnapped at gunpoint in Taanayel on Saturday night as they were heading to the Masnaa border crossing following a two-day visit to Lebanon.

A Turkish court Sunday placed in detention five people suspected of turning over to Syria a founder of the Free Syrian Army who is reported to have since been executed, reports said.

The suspects ordered held by the court in the southern city of Adana include a member of Turkey's National Intelligence Organization (MIT), the Anatolia news agency reported.

Arab and western states are to launch a new bid at the United Nations this week to put pressure on Syria's President Bashar Assad, setting off new diplomatic hostilities between Assad's friends and foes.

Saudi Arabia and Qatar have drawn up a resolution backing an Arab League plan to end the 11-month-old crackdown on protests which could be voted in the U.N. General Assembly this week.

Al-Qaida leader Ayman al-Zawahiri voiced his support for Syria's uprising and urged Muslims in several countries, including Lebanon, to come to the aid of Syrian rebels confronting President Bashar Assad's forces.

"I appeal to every Muslim and every free, honorable one in Turkey, Iraq, Jordan, and Lebanon, to rise to help his brothers in Syria with all that he can," Zawahiri said in a new video message released on jihadist Internet forums, U.S. monitors SITE Intelligence said on Sunday.

A cautious calm prevailed in the northern port city of Tripoli on Sunday after two days of heavy gunbattles between two neighborhoods left at least three people dead and 23 injured.

Media reports said there was no breach of the ceasefire that was reached on Saturday between the rival neighborhoods of Bab al-Tabbaneh, which is Sunni, and the dominant Alawite Jabal Mohsen.

French Foreign Minister Alain Juppe has reportedly asked Premier Najib Miqati that Lebanon not reject a proposal made by his country to form a "Friends of Syria" group.

During a meeting they held in Paris on Friday, Juppe said Lebanon shouldn’t reject the idea during the meeting of Arab League foreign ministers that will be held in Cairo on Sunday, French official sources told pan-Arab daily al-Hayat.

Foreign Minister Adnan Mansour rejected to be a false witness in the meetings of Arab foreign ministers, warning that Lebanon would be harmed if Syria was engulfed by fire.

In an interview with the Kuwaiti al-Rai daily published Sunday, Mansour said: “If we have remarks then we will say them boldly particularly if that decision would threaten the security and stability of Syria.”