Pro-Russian activists in eastern Ukraine are due to consider a proposal by Russian President Vladimir Putin to delay referendums on autonomy.
Separatist leaders in Donetsk and Luhansk say they will put the matter before “people’s councils”.
The votes are due to take place on Sunday and millions of ballot papers have been prepared.
Mr Putin has said putting off the vote could help create the conditions necessary for dialogue.
In what appeared to be a shift in Russian policy, Mr Putin also said this month’s presidential elections in Ukraine were a move “in the right direction”.
His remarks came days after his spokesman said holding such an election would be absurd.
Moscow has vowed to protect the rights of the largely Russian-speaking people in the south and east against what it calls an undemocratic government in Kiev.
Ukraine’s interim authorities have rejected pro-Russian activists’ demands for greater autonomy and sent in troops to seize back official buildings occupied by rebels.
“We respect Putin’s stance,” said Denis Pushilin, a pro-Russian leader in the eastern city of Donetsk.
“He is a balanced politician. Therefore we will submit his proposal to the people’s council.”
In Luhansk, a statement from pro-Russian groups quoted by Russian news agency Ria Novosti said: “We are putting this forward for discussion by all the people because Putin has appealed to supporters of federalisation, therefore a decision will be for all the people of Luhansk.”
The White House said the “illegitimate, illegal” vote should be cancelled rather than postponed.
And Ukrainian interim Prime Minister Arseniy Yatseniuk dismissed Mr Putin’s calls as “hot air”.
The US and the European Union have imposed sanctions against several Russian individuals and small businesses and threatened to impose wider measures if Moscow takes further steps to interfere in Ukraine.
Sunday’s planned referendum was seen as a potential trigger for that.
On Wednesday, President Putin also announced he was ordering Russian troops back from the Ukrainian border.
However, Nato and the Pentagon said they had seen no signs of a Russian pull-back.
On Ukraine’s forthcoming presidential elections, Mr Putin said: “I would like to stress that… while they are a move in the right direction, [they] will not decide anything if all the citizens of Ukraine fail to understand how their rights are protected after the elections are held.”
Unrest in the south and east of Ukraine has worsened since Russia annexed the Crimean peninsula in March.
That followed the ousting of Ukraine’s pro-Russian President Viktor Yanukovych in February by pro-Western protesters.
On Wednesday, pro-Russian separatists took back the city hall in the southern port of Mariupol after it was briefly taken over by Ukrainian government forces.
In that time, 16 activists were arrested and taken to the city’s police station where a violent confrontation erupted between the detainees’ supporters and security forces who fired shots into the air.