Pro-Russia separatists refuse to budge despite international deal to ease tensions

Despite an international deal to de-escalate tensions in Ukraine, pro- Russian separatists in Ukraine are reportedly refusing to abandon public buildings.

Refusing to vacate seized buildings, the self proclaimed separatist leader Denis Pushilin said that it is those aligned with the Kiev-based national government who should vacate all public buildings, not the militants in Donetsk.

According to CNN, Pushilin, the head of a group called the Donetsk People's Republic, addressed reporters on the heels of an agreement Thursday between officials from Ukraine, the United States, the European Union and Russia.

Pushilin said that Russian Foreign Minister Sergey Lavrov did not sign anything for the people, adding that he signed on behalf of the Russian Federation.

Earlier, the US had reportedly threatened Russia with stricter economic sanctions if it did not comply with the new international agreement to help contain the crisis in Ukraine.

During recent talks in Geneva, Russia, Ukraine, the EU and the US had agreed that illegal military groups in Ukraine had to be disbanded, and that those occupying government premises must be disarmed and made to leave.

However, the separatists' spokesman in the city of Donetsk said that the Kiev government was "illegal", and refused to leave the premises until the government stepped down.

Meanwhile, US National Security Adviser Susan Rice, on Friday, warned that if Moscow failed to uphold the deal, a new round of sanctions would focus on "very significant sectors of the Russian economy".