KYIV, Jan 20 — Ukrainian President Volodymyr Zelensky said today there could be no guarantees for the security of Europe as long as regions of his country remained under the control of Russia and pro-Moscow separatists.

"Comprehensive security in Europe is impossible without the restoration of the sovereignty and territorial integrity of Ukraine,” said Zelensky, whose military has been in a simmering conflict with pro-Russian separatists since 2014 when Moscow annexed the Crimean peninsula from Ukraine.

With tens of thousands of Russian troops massed on the Ukrainian border, fears are mounting that a major conflict could break out in Europe.

Moscow insists it has no plans to invade Ukraine but has at the same time laid down a series of security demands—including a ban on Ukraine joining Nato—in exchange for de-escalation.

US Secretary of State Antony Blinken will meet Russia’s Foreign Minister Sergei Lavrov for a new round of security talks in Geneva tomorrow.

"I expect the result of our common efforts, our negotiations with Russia, will be a de-escalation of the situation on the border with Ukraine,” Zelensky said in an address broadcast online.

The conflict with separatists in eastern Ukraine has so far left more than 13,000 dead.

Kiev and its Western allies accuse Russia of supporting the rebels by soldiers and arms—claims which Moscow denies. — AFP