After more than a year of fighting in Syria, the peace plan brokered by international envoy Kofi Annan appeared to be the most serious effort yet to end the bloodletting.

But on a day when Syrian army tanks were supposed to pull back from Syrian cities, opposition groups said there were fresh attacks Tuesday in the central city of Homs and several other cities.

Annan, the former U.N. secretary-general, said the Syrian military has withdrawn from some places, but was also moving into areas that were not previously targeted. Still, he says there is time for his plan to work.

"I believe it is a bit too early to say that the plan has failed," Annan said. "The plan is still on the table, and it is a plan we are all fighting to implement."

Annan Visits Refugee Camp

Annan, who is a joint U.N. and Arab League envoy, visited Syrian refugees in Turkey on Tuesday and said he heard heart-wrenching stories about women and children uprooted from their homes and fired upon as they fled. He said he's working on getting international monitors on the ground and is calling for an end to the bloodshed before Syria "plunges into the abyss."

"There should be no preconditions for stopping the violence," he said. "That's something we need to do for the people and for the country concerned."

Syria wanted guarantees that opposition forces would abide by the Annan plan, a move the U.S. government described as a stalling tactic.

At the United Nations, U.S. Ambassador Susan Rice said there will soon be a moment of truth when countries will have to think about stepping up the pressure on Syrian President Bashar Assad.

"It is outrageous, but by no means unexpected or surprising, that the government has yet again made commitments and broken them," she said.

Syrian Envoy Seeks Support In Russia

Russia's position will be key. In Moscow on Tuesday, Russian Foreign Minister Sergei Lavrov was nudging his Syrian counterpart to implement the Annan plan.

According to Lavrov, the Syrians should be more decisive in implementing the plan.

Some analysts said it appeared the Russians, who have long supported the Syrian government, were sounding increasingly frustrated with Damascus.

"It looks like the Syrian government is thumbing its nose at the Russians just like it is the rest of the world," said Anne-Marie Slaughter, who was the State Department's policy planning director before returning to Princeton University last year to teach international relations. She thinks the best option now is something that's been under discussion for months — setting up safe zones for Syrian civilians.

"This has been a game of 'After you,' 'No, after you,' where the Turks have said they couldn't move without the U.N., the U.N. couldn't go without Russia, the U.S. wasn't going to move unless the Turks and the Arabs moved," she said. "So everybody has pointed to everybody else."

Slaughter is hopeful that is changing as everyone sees the Annan peace plan falter.

"We have to recognize that unless we put together a coalition that is willing at least to create a safe zone, we are looking at a civil war that is going to spill over borders," she said. "It's going to result in increasing sectarianism and fragmentation in Syria, increasing instability in the region, harm to our interests, and ultimately exactly the kind of situation we most want to prevent right in the heart of the most sensitive region in the world."

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