Pro-Russian insurgents in Ukraine's east who have been occupying government buildings in more than 10 cities said Friday they will only leave them if the interim government in Kiev resigns.

Denis Pushilin, a chairman of the self-appointed Donetsk People's Republic, told reporters that the insurgents do not recognize the Ukrainian government as legitimate.

Ukraine and Russia on Thursday agreed to take tentative steps toward calming tensions along their shared border after weeks of conflict. But Pushilin, speaking at the insurgent-occupied regional administration's building in Donetsk, said the deal specifies that all illegally seized buildings should be vacated, and in his opinion the government in Kiev is also occupying public buildings illegally.

"This is a reasonable agreement but everyone should vacate the buildings and that includes Yatsenyuk and Turchynov," he said referring to the acting Ukrainian prime minister and president. He reiterated the call for a referendum that he said will allow "self-determination of the people."

The deal agreed in Geneva calls for disarming all paramilitary groups and the immediate return of all government buildings seized across the country. Russian Foreign Minister Sergey Lavrov at the time emphasized that that applies to all parties, including protesters in Kiev.

Russia did not demand that that the new government leave the buildings, even though Moscow has not recognized it.

The Ukrainian government said in response that it could take "more concrete actions" next week if the separatists do not end their occupations of public buildings. "Hopefully, if those people are ready to leave the buildings, to surrender weapons, today, tomorrow, so we can encourage the OSCE mission to negotiate, to mediate and implement this," Ukraine's Foreign Minister Andriy Deshchytsia said. "But if this will not start in a few days, I think that after Easter there will more concrete actions."

The Russian foreign ministry also had no immediate comment, but pro-Russian Ukrainian presidential candidate Oleh Tsaryov, whose statements often echo Moscow's stance, said in comments carried by the Russian state RIA Novosti news agency on Friday that Right Sector activists should be the first to lay down their arms and that Ukrainian servicemen who have unsuccessfully tried to regain control over parts of eastern Ukraine should return to their quarters.

Prime Minister Arseniy Yatsenyuk told the parliament Friday morning that the government has drafted a law that would offer amnesty to all those who will be willing to lay down their arms and leave the occupied government buildings.

Kiev-based political analyst Vasim Karasyov said Ukraine's fledgling government does not have the resources to resolve the stand-off in eastern Ukraine militarily, so it is going to have to negotiate with the pro-Russian protesters.

Kiev "should finally listen to the demands of those people, what they want," he said. "They don't even know what their demands are; maybe they are reasonable. The government in Kiev is pretending as if there are no problems in the east."

Russian disappointment

President Barack Obama said the meeting in Geneva between Russia, Ukraine and Western powers was promising but that the United States and its allies were prepared to impose more sanctions on Russia if the situation fails to improve.

"There is the possibility, the prospect, that diplomacy may de-escalate the situation," Obama told reporters.

"The question now becomes, will in fact they use the influence they've exerted in a disruptive way to restore some order so that Ukrainians can carry out an election and move forward with the decentralization reforms that they've proposed," he said at the White House.

Ukraine's government promises to devolve power to the regions and protect people's rights, notably in the east, to use the Russian language in public life. But it rejects calls for a federal structure that it says could lead to permanent Russian interference in the east and eventually break up the country.

U.S. Secretary of State John Kerry said in Geneva that if by the end of the weekend there were no signs that pro-Russian groups were pulling back, there would be costs for Moscow, a reference to further EU and U.S. sanctions

Russia said the threat of new sanctions against Moscow by Washington was "completely unacceptable". 

The Foreign Ministry accused U.S. officials of seeking to whitewash what it said was the use of force by the Ukrainian government against protesters in the country's mainly Russian-speaking eastern provinces.

"American officials sounded ultimatums, and tried to threaten us with new sanctions, which is completely unacceptable," the ministry said in a statement.
President Barack Obama said the meeting in Geneva between Russia, Ukraine and Western powers was promising but that Washington and its allies were prepared to impose more sanctions on Russia if the situation fails to improve.

Moscow described Washington's stance as one-sided and said it was "disappointed" by its remarks after the talks, which seemed to offer the best hope of resolving a confrontation that has dragged relations to their lowest ebb since the Cold War.

"The blame for the Ukrainian crisis and its current aggravation is unreasonably being placed on Russia," the ministry said.