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By Steve Gutterman
ST PETERSBURG, Russia, June 22 (Reuters) - Russian Foreign Minister Sergei Lavrov said on Friday that he had urged Syria's government to "do a lot more" to implement envoy Kofi Annan's U.N.-backed peace plan, but that foreign countries must also press rebels to stop the violence.
After talks with Syria's foreign minister, Lavrov said Syria's government was prepared to withdraw forces from cities and towns simultaneously with rebels and suggested Moscow would seek support for such an agreement among other nations.
His remarks appeared aimed to indicate that Moscow is putting pressure on President Bashar al-Assad's government while at the same time making clear his opponents share the blame for persistent violence.
"We called on them to back their statement of readiness to carry out Kofi Annan's plan with action," Lavrov said of his meeting with Syrian Foreign Minister Walid al-Moualem on the sidelines of an economic forum in St. Petersburg.
"They have already done a lot but they could and must do a lot more," Lavrov told state-run Rossiya-24 television.
Syrian government forces have killed more than 10,000 people since 15 months of violence began with a crackdown on pro-democracy protesters last year. They were supposed to withdraw from cities and towns under Annan's peace plan, which called for a ceasefire to begin on April 12.
Lavrov said he hoped an international meeting on Syria which could be held soon would produce an agreement "under which government forces and the armed opposition must withdraw simultaneously from cities and towns under the control of international observers. The minister told me that today."
"Now we need to make it so that the other side is also ready for this," Lavrov said.
However, U.N. observers sent to Syria to monitor the ceasefire deal halted operations on Saturday, and it is unclear whether the U.N. Security Council will extend the mission's mandate when it expires on July 21.
Lavrov also lashed out at the United States, saying he would not make any excuses for continued Russian arms deliveries to Syria when he meets U.S. Secretary of State Hillary Clinton in St. Petersburg late next week.
"I do not plan to justify myself," Lavrov said. "I do not plan to touch on this subject. If my colleague is interested in these questions, I will answer that we do not plan to justify ourselves."
Lavrov acknowledged on Thursday that a cargo ship that changed course this week after losing its insurance cover off Scotland, was carrying three repaired Russian combat helicopters and air defence systems to Syria. (Additional reporting by Alissa de Carbonnel in Moscow; Writing by Steve Gutterman; Editing by Timothy Heritage and Myra MacDonald)