The UN Security Council on Tuesday condemned "in the strongest terms" attacks by demonstrators on the U.S. and French embassies in Damascus.
Both Washington and Paris sharply denounced Syrian President Bashar Assad, who has been trying for four months to stamp out a broad popular revolt with troops and tanks.
"He has lost legitimacy by refusing to lead the transition" to democracy, White House spokesman Jay Carney told reporters, further sharpening U.S. rhetoric against the Syrian leader over his forces’ harsh crackdown on protesters.
On Monday, U.S. Secretary of State Hillary Clinton had told reporters: "We have absolutely nothing invested in him remaining in power.”
A Security Council statement read to media on Tuesday by Germany's UN Ambassador Peter Wittig, this month's president, called on Syrian authorities to protect diplomatic property and personnel.
French Prime Minister Francois Fillon had earlier accused Russia and China of trying to block a U.N. resolution on Syria, saying it was "intolerable that the Security Council should stay silent on such a tragedy".
Syria's U.N. ambassador accused the United States and France on Tuesday of distorting and exaggerating facts about attacks by demonstrators this week on their embassies in Damascus.
The envoy, Bashar Ja'afari, told reporters that Syria had had sought to protect the embassies and that some demonstrators involved in Monday's events had been arrested and would be brought to justice.
The Syrian state news agency SANA said Clinton's remarks were "another proof of the U.S.'s flagrant intervention in Syria's internal affairs".
"The legitimacy of Syria's leadership is not based on the United States or others, it stems from the will of the Syrian people," it said.
Crowds broke into the U.S. embassy in Damascus on Monday and tore down plaques, while security guards using live ammunition drove crowds away from the French embassy.
The attacks followed protests against a visit by U.S. Ambassador Robert Ford and French envoy Eric Chevallier to the city of Hama, now the focus of the uprising against Assad.
Inspired by the protests that unseated the leaders of Egypt and Tunisia, Syrians have been taking to the streets by the thousands since March, calling for more political freedom and an end to corruption and poverty.
Assad has responded with a mixture of force and promises of reforms. He sent his troops and tanks to numerous cities and towns to crush protests, and thousands have been arrested.
Despite these harsh measures, Assad has also granted citizenship to tens of thousands of Kurds, lifted the draconian state of emergency, freed hundreds of prisoners and called for a national dialogue.
A two-day meeting aimed at setting the framework for national dialogue and discussing legislation that would allow a multi-party system and constitutional amendments issued its final statement on Tuesday, endorsing the formation of a committee to rewrite the constitution.
Western governments have condemned Assad's violence against protesters, however they have limited their actions against the oppressive regime to sanctions against top officials, a far cry from the military intervention against Muammar Gadhafi in Libya.
The administration of U.S. President Barack Obama has steadily toughened its rhetoric on Assad as Syrian security forces continue to crack down on protests. Until Monday, however, it had refrained from saying Assad had lost legitimacy.
Washington has imposed targeted sanctions on Assad and members of his inner circle, and has said it is working with its allies to build international consensus for further pressure on his government.
Support for Assad
Assad retains the support of Iran and Lebanon's Hezbollah, as well as substantial portions of the minority Alawite community from which his family springs.
"If the Americans think he has lost legitimacy, this doesn't mean he has lost legitimacy, it means the Americans think he has lost legitimacy," Rami Khouri, a political analyst based in neighboring Lebanon, told Reuters.
"When Ford visited Hama, the dynamic changed. Clinton's remarks have simply raised the temperature."
Syria said Ford had sought to incite protests. The State Department denied this and said Ford had toured Hama to show solidarity with residents facing harsh security measures.
Hama, a city of 700,000 people, was the scene of a 1982 massacre that came to symbolise the ruthless rule of the late president Hafez Assad, and has staged some of the biggest protests in 14 weeks of demonstrations against his son Bashar.
Human rights groups say at least 1,400 civilians have been killed since the uprising began in March.
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