BEIRUT » Syria’s military today declared that the U.S.-Russian brokered cease-fire was over, shortly after the Russian military said it was “meaningless” to continue observing the agreement. The Syrian declaration and Moscow’s statement came amid mounting violations and an exchange of accusations between Russia and the United States.

Soon after, the U.S. said it’s prepared to extend the fractured ceasefire despite numerous violations and the Syrian military’s announcement.

It was unclear this evening whether the agreement — which has brought a brief respite to the war-torn country — would truly collapse on the ground. Shortly before the Syrian military declaration, U.S. Secretary of State John Kerry told reporters on the sidelines of the U.N. General Assembly that the truce was “holding but fragile.”

Residents of eastern Aleppo reported the resumption of airstrikes in their besieged areas. There were no immediate reports of casualties. The government also said it repelled an insurgent attack on areas it controls south of Aleppo.

In the wake of the Syrian announcement, Kerry expressed annoyance at Damascus and Moscow’s handling of the cease-fire.

“It would be good if they didn’t talk first to the press but if they talked to the people who are actually negotiating this,” he said. “As I said yesterday, (it’s) time to end the grandstanding and time to do the real work of delivering on the humanitarian goods that are necessary for access.”

But Kerry also acknowledged that the first stage of the truce — which called for a week of calm and the delivery of humanitarian aid to several besieged communities — had never really come to fruition.

The State Department later said that it was ready to work with Russia to strengthen the terms of the agreement and expand deliveries of humanitarian aid.

Spokesman John Kirby said Russia, which is responsible for ensuring Syria’s compliance, should clarify the Syrian position.

A Russian Foreign Ministry statement late tonight appeared to signal that the deal could still be salvaged, saying that the failure by the rebels in Syria to respect the cease-fire threatens to thwart the agreement.

The cease-fire came into effect on Sept. 12. Under terms of the agreement, the successful completion of seven days of calm and humanitarian aid deliveries would be followed by an ambitious second-stage plan to set up a joint U.S.-Russian coordination center to plan military strikes against the Islamic State group and a powerful al-Qaida-linked militant faction.

But from the start, the truce has been beset by difficulties and mutual accusations of violations.

Aid deliveries to the besieged eastern districts of Aleppo, a key point in the truce agreement, have not reached their destination. The U.N. accused the government of obstructing the delivery while Russian officials said rebels opened fire at the delivery roads.

Rebel forces and activists say government planes have bombed areas that are under the truce agreement, including rebel-held parts of Aleppo. At least 22 civilians were killed in government bombings over the last week, according to the Britain-based Syrian Observatory for Human Rights, an opposition monitoring group. The group said four civilians were killed in government-held areas. There were no independent reports of deaths of civilians on the government-side since the cease-fire came into effect.

By today, both the Syrian government and prominent opposition activists were speaking of the truce as if it had already failed.

George Sabra, of the opposition High Negotiations Committee, told The Associated Press today that the truce has been repeatedly violated and did not succeed in its main objective — opening roads for aid to enter besieged rebel-held areas.

“Hundreds of thousands of people in Aleppo are waiting for this truce to allow aid to enter the city,” he said, adding that there are aid trucks still waiting on the Turkey-Syria border. “I believe that the truce is clinically dead.”

The Syrian military statement placed the blame squarely on the rebel groups. Damascus refers to all armed opposition groups as terrorists.

“This step (cease-fire) was to constitute a real chance to stop the bloodshed. But the armed terrorist groups didn’t take it seriously and didn’t commit to any of its articles,” the military command statement said. “The armed terrorist groups took advantage of the declared truce system and mobilized terrorists and weapons and regrouped to continue its attacks on civilian and military areas.”

One of the major rebel groups in Syria, Nour el-Din el-Zinki, said soon after the Syrian military declaration that the government, Russia and Iran, another major ally of President Bashar Assad, are responsible for the truce’s failure.

“The regime of Bashar Assad had no real intention to commit to the truce. Instead it worked to undermine it with organized violations during the week as well as preventing aid from reaching Aleppo,” the group said in a statement sent to reporters.

Earlier today Lt. Gen. Sergei Rudskoi of the Russian military’s General Staff said in a briefing that Damascus had fulfilled its obligations.

“With the rebels failing to fulfill conditions the cease-fire agreement, we consider its unilateral observance by the Syrian government forces meaningless,” Rudskoi said.

Rudskoi said the rebels have violated the truce 302 times since it took effect a week ago, killing 63 civilians and 153 Syrian soldiers. The opposition reported today 254 violations by government forces and their allies since the truce started.

The current tensions come on the heels of the weekend air strike by the U.S.-led coalition on Syrian army positions near Deir el-Zour. Syria and Russia blasted Washington over the attack.

The Saturday airstrikes involved Australian, British and Danish warplanes on Syrian army positions. The U.S. military said it would not intentionally hit Syrian troops, and that it came as it was conducting a raid on IS positions.

Russia’s military has said that it was told by the Syrian army that at least 62 Syrian soldiers were killed in the Deir el-Zour air raid and more than 100 wounded. The Observatory gave a different death toll, saying 90 troops were killed in the strikes.

Assad said today the airstrikes of the U.S.-led coalition against his troops was meant to support the Islamic State group, calling the attack a “blatant American aggression.”