BEIRUT — Syrian troops defied a U.N.-brokered cease-fire plan on Tuesday, launching fresh attacks on rebellious areas, but special envoy Kofi Annan said there was still time to salvage a truce that he described as the only chance for peace.
More than a year into the Syrian uprising, the international community has nearly run out of options for halting the slide toward civil war. On Tuesday, Annan insisted his peace initiative remains "very much alive" — in part because there is no viable alternative.
The U.N. has ruled out any military intervention of the type that helped bring down Libya's Moammar Gadhafi, and several rounds of sanctions and other attempts to isolate President Bashar Assad have done little to stop the bloodshed.
"If you want to take (the plan) off the table, what will you replace it with?" Annan told reporters in Hatay, Turkey, where he toured a camp sheltering Syrian refugees.
Facing a Tuesday deadline to pull back its tanks and troops, the Syrian government had said it was withdrawing from certain areas, including the rebellious central province of Homs. But France called the claims a "flagrant and unacceptable lie," and activists said there was no sign of a withdrawal.
Residents of Homs reported some of the heaviest shelling in months.
"Hundreds of mortar rounds and shells were falling around all day," resident Tarek Badrakhan told The Associated Press. He said a makeshift hospital housing wounded people and dozens of corpses was destroyed in the shelling.
"It's now on the ground," he said.
In a letter to the U.N. Security Council, obtained by The Associated Press, Annan said Syria has not pulled troops and heavy military equipment out of cities and towns, and that the regime's last-minute conditions put the entire cease-fire at risk.
The council strongly backed Annan, with all 15 members — including Syrian allies China and Russia — urging Syria's leaders to halt all military action so a cease-fire can take effect at 6 a.m. on Thursday, as called for by Annan's plan. It also called on the opposition to stop all violence if the Syrian forces halt attacks.
"Obviously, members of the council are unified in their grave concern that this deadline has passed and the violence has not only continued but over the last 10 days has intensified," said Susan Rice, U.S. ambassador to the U.N. and this month's council president.
Secretary of State Hillary Rodham Clinton said Annan's report made clear that "Assad is not complying with the commitments that he made under the six-point plan and that, in fact, violence has only gotten worse over this last week."
French Foreign Minister Alain Juppe accused Assad of lying and flouting Syria's commitments. "Not only has the use of heavy weapons not ended ...but what was presented as a withdrawal is in fact only a thinly disguised redeployment," he said in a statement.
According to Annan's peace plan, the pullback of Syrian forces was supposed to be followed by a full cease-fire by all within 48 hours. The halt in fighting would then pave the way for an observer mission and talks between both sides over the country's future.
After 13 months of bloodshed, a revolt that began as a mostly peaceful movement against Assad's stagnant and entrenched regime has morphed into an insurgency.
The U.N. estimates more than 9,000 people have been killed since the uprising began, and the toll climbs every day. Regime forces assault their opponents with tanks, machine guns and snipers, and the Free Syrian Army rebel group launches frequent attacks against government targets, killing soldiers and security forces.
Syria's main opposition group said about 1,000 people have been killed in regime attacks in the last eight days alone, a figure that could not be independently confirmed.
The conflict is among the most explosive of the Arab Spring, in part because of Syria's web of allegiances to powerful forces including Lebanon's Hezbollah and Shiite powerhouse Iran.
Western leaders have pinned their hopes on Annan's diplomatic pressure, with the U.S. and others unwilling to get deeply involved in another Arab nation in turmoil — particularly one as unpredictable as Syria. Even though Washington has a clear interest in seeing Assad go, in part because it would be a blow to Iran, the Obama administration is reluctant to use force.
Russia and China had blocked strong action by the U.N. Security Council, giving Assad a significant layer of protection as his crackdown continues.
Republican U.S. Sen. John McCain, who has called on the Obama administration to launch U.S. airstrikes to end Assad's crackdown, said Russia and China should be ashamed of their stance.
"Shame on you for blocking the efforts that could be made by the U.N. to stop the slaughter," he said in Turkey.
With the conflict at a stalemate, Annan's plan was hailed as a possible diplomatic breakthrough, even though there was skepticism from the start that the deadline would hold.
Annan, working on behalf of the U.N. and the Arab League, secured the support of Russia and China for his cease-fire plan, and he went to Iran on Tuesday to press officials there for support as well.
But a swift halt to the fighting is unrealistic, analysts say.
"Full and timely implementation of Annan's plan almost surely was never in the cards," the International Crisis Group said in an analysis of the Syrian conflict. "But that is not a reason to give up on diplomacy in general or the Annan mission in particular."
The priority must be to keep the conflict from getting worse, the report said.
"In the absence of a realistic, workable alternative, the best chance to achieve that is still to build on aspects of the envoy's initiative and achieve broad international consensus around a detailed roadmap," the report said.
Still, critics have accused Assad of playing for time since he accepted the six-point truce agreement on March 27.
Soon after the deadline was agreed, regime forces stepped up attacks on opponents.
On Monday, the violence in Syria spilled across two borders when regime forces opened fire, killing a TV journalist in Lebanon and at least two people in a refugee camp in Turkey. The bloodshed was a sign of how easily Syria's neighbors could be drawn into a wider conflict.
The regime also began making last-minute demands.
On Sunday, Syrian Foreign Minister Walid Moallem said the military could not withdraw without written guarantees that the rebels would lay down their arms. He raised another condition Tuesday, saying that the cease-fire must start simultaneously with the deployment of the international observer mission.
In his news conference, Annan said violence must stop without preconditions.
"I had hoped that by now, we would have been much further ahead," he said. He included opposition fighters in his appeal for calm, but directed most of his criticism at the Syrian government, saying that it is "time the military go back to their barracks."
On Tuesday, during a visit to Moscow, Moallem said the Syrian military was withdrawing from some areas.
French Foreign Ministry spokesman Bernard Valero dismissed the claim as "a new expression of this flagrant and unacceptable lie." British Foreign Secretary William Hague accused Damascus of using the deadline "as a cover for intensified military efforts to crush Syria's opposition."
Even Moscow was politely critical. Russian Foreign Minister Sergey Lavrov said Syria's "efforts to implement the plan could have been more active and resolute."
On the ground, activists said there were scant signs that the regime was withdrawing.
Syrian tanks and soldiers remained in most major flashpoint towns and cities across the country, with military operations reported in the Damascus suburbs, the central regions of Homs and Hama, Idlib and Aleppo in the north and Daraa in the south.
Amateur video posted online showed a tank in the Damascus suburb of Douma with the slogan "Assad's shield" painted on the side.
Syrian activists said dozens of people were killed across the country, including up to 19 troops killed in rebel ambushes or in clashes with opposition forces.
"Soldiers are not being withdrawn from towns and villages," Fadi al-Yassin, an activist in Idlib province close to Turkey, told the AP by telephone. "On the contrary, reinforcements are being sent."
Associated Press writers Bassem Mroue and Karin Laub in Beirut, Edith M. Lederer at the United Nations, Frank Jordans in Geneva, Selcan Hacaoglu in Ankara, Turkey, and Vladimir Isachenkov and Nataliya Vasilyeva in Moscow contributed to this report.