U.S. President Barack Obama says Syrian President Bashar al-Assad is “losing legitimacy in the eyes of his people,” and has missed “opportunity after opportunity” to present genuine reforms.

Mr. Obama told CBS News Tuesday the Syrian government has perpetrated what he called an “unacceptable degree of brutality” on peaceful demonstrators protesting Mr. Assad's authoritarian rule.

Syria has sharply criticized similar remarks by U.S. Secretary of State Hillary Clinton, saying her comments were “further evidence” of “blatant U.S. interference” in Syria's internal affairs.

Clinton said Monday that Mr. Assad has “lost legitimacy” and is “not indispensable.” She also said the U.S. has “nothing invested in him remaining in power.”

Meanwhile, residents in eastern Syria say a bomb exploded late Tuesday in Tayanah near the Iraqi border, damaging a gas pipeline. State television said there were no casualties and only minor damage from the blast.

Also Tuesday, the United Nations Security Council condemned in the “strongest terms” this week's attacks against the U.S. and French embassies in Damascus.

In his CBS interview, Mr. Obama said the U.S. has sent “a clear message” that “nobody can be messing with our embassy.” He said Syria has been warned that Washington will take “whatever actions necessary” to protect its overseas missions.

On Monday, loyalists to Mr. Assad mobbed the embassy compound, broke windows and briefly raised a Syrian flag. The U.S. State Department said Tuesday the embassy is operational, and U.S. and Syrian officials are working to repair the damage.

Security guards at the French embassy fired shots into the air on Monday to keep demonstrators from entering the grounds. Officials said three embassy staffers were injured during the unrest.

The incidents took place after U.S. Ambassador Robert Ford and French Ambassador Eric Chevallier traveled to the flashpoint city of Hama last week to show solidarity with residents facing a military crackdown on dissent.

In another development, Syria wrapped up a three-day session of a government-organized “national dialogue” on Tuesday. The state news agency says the participants issued a statement in which they said stability and a greater commitment to reforms are high priorities.

Syria's main opposition groups did not participate in the talks.

Rights groups say Syrian security forces have killed at least 1,600 civilians during the crackdown, while the government blames the violence on terrorists and Islamists who it says have killed hundreds of security personnel.