"There cannot be bargaining over compliance of the [ceasefire] conditions," Estonian Prime Minister Taavi Roivas has said, insisting the deal must be fulfilled to the last letter."Cooperation elsewhere does not mean for Europe concessions in its neighbourhood," he told parliament on Tuesday, Ukraine Today reports.

But the Paris attacks and last month's downing of a Russian airliner over Egypt, both claimed by Islamic State, have created a sense that Western capitals and Moscow have a common interest in battling the militants.

This has increased pressure for greater cooperation, effectively easing Moscow's international isolation.

Leaders of nine central and eastern European and Baltic states declared earlier this month that they were gravely concerned by Russia's "continuing aggressive posturing" and backed a sustainable NATO military presence in the region.

"The Russian-made crisis in Ukraine cannot disappear from the agenda," Lithuanian Foreign Minister Linas Linkevicius said Monday after a meeting of EU foreign ministers in Brussels.

See unian.info’s video section for more of the latest news from Ukraine in video from Ukraine Today, Ukraine’s 24-hour English-language news channel.