The Syrian foreign ministry called in the French and U.S. ambassadors on Sunday to deliver a "strong protest" over their visit to the flashpoint central city of Hama last week, state media said.

"The ministry called in the U.S. and French ambassadors to deliver a strong protest against their visit to Hamas without prior authorization... which constitutes a flagrant interference in Syria's domestic affairs," the official SANA news agency said.

Turkish Foreign Minister Ahmet Davutoglu will visit Iran Sunday to discuss a wave of unrest shaking Middle East countries, a senior Turkish diplomat said.

Davutoglu was to travel to Tehran after completing talks in Saudi Arabia, where he flew Saturday evening, the diplomat, who accompanied the minister on the trip, told AFP by telephone.

Syria opened a "national dialogue" on Sunday that it hailed as a step towards multi-party democracy after five decades of Baath party rule, but its credibility was undermined by an opposition boycott.

Some 200 delegates, including independent MPs and members of the Baath party, in power since 1963, observed a minute's silence in memory of the "martyrs" before the playing of the national anthem.

Interpol issued its highest-level international alerts against four Hizbullah men indicted in the 2005 slaying of former Prime Minister Rafik Hariri, a Lebanese security official said Saturday.

The Interpol red notices were issued at the request of the Netherlands-based Special Tribunal for Lebanon, said the official, who requested anonymity in line with official regulations.

Security forces killed at least 15 people and arrested more than 200 people in Syria, activists said, as Human Rights Watch denounced on Saturday a "deliberate policy" to disperse protesters with deadly force.

The deaths came as Damascus accused the U.S. envoy of inciting violence in Hama -- where nearly half a million people protested on Friday -- a charge roundly denied by Washington which accused the Syrian embassy of spying on demonstrators in the United States.

Washington summoned the Syrian ambassador for talks this week after reports that embassy staff had filmed U.S. protests against the crackdown in Syria, the State Department said Friday.

Ambassador Imad Mustapha was called in to meet with top State Department officials "to express a number of our concerns with the reported actions of certain Syrian embassy staff in the United States," the agency said.

President Michel Suleiman has denied that he would visit Damascus along with Premier Najib Miqati, saying however that it was the PM’s duty to travel to Syria.

In remarks to Ad-Diyar daily published Saturday, Suleiman said: “The prime minister’s visit is a duty and is possible at any time but it’s up to him to decide the appropriate timing.”

Both the U.S. and French ambassadors to Syria were in the protest hub of Hama on Friday to observe anti-regime rallies there as nearly half a million people demonstrated in the flashpoint central city.

The move prompted the Syrian government to accuse the U.S. ambassador to Damascus, Robert Ford, of meeting "saboteurs" in Hama and inciting protests against President Bashar al-Assad.

Lebanese Forces leader Samir Geagea slammed on Thursday the new government, saying that it does not represent Lebanon and will set the country back to a time before the 2005 Cedar Revolution.

He said during a dinner for Lebanese expatriates in Abu Dhabi: “We will work with all possible democratic means to topple this cabinet.”

The U.S. ambassador to Damascus is visiting the flashpoint Syrian city of Hama and plans to observe mass demonstrations Friday against President Bashar al-Assad's regime, the State Department said.

Last Friday, an anti-regime rally brought out half a million people in Hama, according to pro-democracy activists. The security services did not intervene and Assad fired the city's governor the next day.