The United Nations Security Council called off a vote Friday on a resolution calling for a 30-day cease-fire in Syria as the government bombed the Damascus suburbs for a sixth day.

After a vote was scheduled and delayed three times, the Security Council members were unable to settle on language that could gain Russia’s support. As a permanent member of the council, Russia has veto power, and has used it 11 times to protect the government of Syrian President Bashar al-Assad.

A new vote has been scheduled for Saturday.

Moscow effectively blocked a cease-fire vote on Thursday, when its ambassador, Vassily Nebenzia, said a draft proposal sponsored by Sweden and Kuwait was unrealistic and proposed several amendments.

Diplomats said Russia sought an end to the violence “as soon as possible” and a rebuke of rebels shelling Damascus.

The cease-fire proposal it objected to would have taken effect within 72 hours in Eastern Ghouta, the suburb where government missiles and bombs have bombarded rebel positions in what appears to be a full-force offensive to retake control. Hundreds of people have been killed in the last week, many of them civilians.

Almost 400,000 residents in the area have been subjected to an unrelenting barrage of barrel bombs, mortars, rockets and airstrikes. Humanitarian workers and U.N. officials have called the situation there the worst experienced by Syrians in seven years of war.

U.N. officials have compared the situation to a siege from medieval times. Only three convoys carrying emergency supplies have gotten through in the past three months. At least 700 sick and injured people are believed to be in need of medical evacuation to hospitals only a few miles away in Damascus.

A cease-fire would allow deliveries of food and medicine, and the evacuations. As monitors reported more deaths in Eastern Ghouta on Friday, world leaders tried to pressure and cajole Moscow into backing a temporary halt to the violence.

President Trump said in a news conference that the Syrian government and its Russian and Iranian backers were responsible for the ongoing death and devastation.

“I will say what Russia and what Iran and what Syria have done recently is a humanitarian disgrace,” Trump said. “What those three countries have done to those people is a disgrace.”

German Chancellor Angela Merkel and French President Emmanuel Macron sent a joint letter to Russian President Vladi­mir Putin, saying it was time for action and asking for his support.