"We hope that their sense of humanity and compassion will encourage them to join us in pressing the Assad regime to silence its guns," she said.
The entreaties failed to make an immediate impression on Moscow. Foreign Minister Sergey Lavrov instead drew attention to a months-old Russian resolution demanding that Syria's government and the opposition hold talks on reforms. The Russian approach would keep the levers of power in Assad's hands, while requiring his opponents to end their rebellion.
"I don't think there is a need for any new initiatives," Lavrov said Monday. He said other countries "shouldn't expect one another to take any action, but sit down together and decide what steps need to be taken so that the Syrians stop shooting at each other."
Syria is Russia's primary ally in the Middle East, having maintained close ties with Damascus since the Cold War, when the Arab country was led by the current leader's father, Hafez Assad. Putin, Russia's prime minister for the past four years, called last week for government and opposition forces to pull out of besieged cities, accusing the West of encouraging the rebels to fight by refusing to make that demand.
Western countries, meanwhile, added to the pressure and isolation against Assad on Monday.
The Obama administration added Syria's state television and radio to a U.S. sanctions list for its role in supporting the crackdown, while Canada joined the list of governments that have closed their embassies in Damascus to protest the violence.
McCain's call for airstrikes was a marked change from his remarks last month, when he said the U.S. should find ways to help the Syrian people without putting American "boots on the ground." Then, he said the options included providing medical care and technical assistance to safe havens for refugees of the violence.
He had since called for arming Syria's rebels, another step the Obama administration is hesitant to take. It fears a further militarization of Syria, and says the government's superior firepower in the form of tanks and artillery means funneling weapons to Assad's opponents may neither save lives nor accelerate the end of the regime.
Associated Press writers Geir Moulson in Berlin and Laurie Kellman in Washington contributed to this report.
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