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.

A visiting Syrian opposition delegation urged Russia on Tuesday to use its diplomatic clout to convince President Bashar al-Assad to give up the use of force against civilians.

"Russia can use its leverage on the Syrian regime to send a clear message that this way of behavior is unacceptable," said rights advocate Radwan Ziadeh, who is head of Damascus Center for Human Rights Studies in Washington.

Syrian President Bashar al-Assad's regime has called members of the opposition and intellectuals for July 10 talks on the wave of protest sweeping the country, the official SANA news agency reported Monday.

"The mechanism put in place recently for the national dialogue will invite the authorities, intellectuals and political personalities to a July 10 meeting to debate in particular amendments to the Constitution, especially Clause 8," it said.

Syrian President Bashar al-Assad spoke Tuesday of the legitimate demands of his people during a meeting with visiting U.S. congressman Dennis Kucinich, SANA state news agency said.

Assad told the anti-war Democratic Representative of "current events in Syria and the implementation of reforms" during their talks in Damascus, the agency reported.

Syria's flailing economy could prove the tipping point for the autocratic regime of Bashar al-Assad as he seeks to quell a pro-democracy revolt posing a major threat to his rule, analysts say.

"There are some wild cards left in Syria, and the economy is one of them," said one Western diplomat, speaking from Damascus.

U.N. leader Ban Ki-moon said Wednesday that Syrian President Bashar al-Assad lacked "credibility" and urged the U.N. Security Council to overcome divisions on the Syria crisis.

"I do not see much credibility (in) what he has been saying," Ban told a small group of reporters in an interview to mark his reelection as secretary general.

U.N. Secretary General Ban Ki-moon urged Syrian President Bashar Assad on Tuesday to make credible reforms "without delay," after the Syrian leader offered a national dialogue to end months of anti-regime protests.

"He urges the president to carry on these reforms without delay and in a way that is both genuine and credible," Ban's spokesman Martin Nesirky said.

Turkish President Abdullah Gul has said that Syrian President Bashar al-Assad should transform the autocratic regime in his country into a multi-party system, following a televised address by the Syrian leader to the nation Monday.

Gul told reporters late on Monday that Assad’s speech was “not enough.”

President Bashar al-Assad has reached "a point of no return," French Foreign Minister Alain Juppe said Monday following the Syrian leader's speech to his troubled nation.

"Some believe there's still time for him to change his ways and commit to a (reform) process," Juppe said after Assad suggested in a televised speech that dialogue could lead to a new constitution.

Pro-democracy activists said the three-month-old "revolt" in Syria must go on after a speech by President Bashar al-Assad on Monday that they said only deepened the crisis.

The Coordination Committee, an umbrella group of activists calling for street protests, called for "the revolution to carry on until all its aims have been achieved."