The United Nations Security Council will vote on Friday on a draft resolution demanding a 30-day truce in Syria to allow aid deliveries and medical evacuations, but it was not immediately clear if the text had won the support of Syrian ally Russia.
The vote comes as warplanes pounded eastern Ghouta, the last rebel enclave near Syria's capital, for a fifth day running.
UN Secretary-General Antonio Guterres appealed on Wednesday for an immediate end to "war activities" there.
Russia on Thursday proposed amendments to the resolution drafted by Sweden and Kuwait, arguing that the language was unrealistic and that the 15-member Security Council could not simply impose a truce on Syria without consulting the parties.
It was not immediately clear what changes were made to the text. The council is due to vote at 11 a.m. (1600 GMT) on Friday, said Kuwait's U.N. mission, president of the council for February.
A resolution needs nine votes in favor and no vetoes by Russia, China, the United States, Britain or France. Russia has cast 11 vetoes on possible Security Council action on Syria since its civil war began in 2011.
Previous attempts at a cessation of hostilities in Syria have quickly unraveled.