REUTERS

"Further escalation of the situation by the Russian Federation should not be ruled out. According to available intelligence data, there is a clear threat for invasion and seizing of Mariupol and Berdyansk. Further aggressive acts and provocations by the FSB border guard service and Russian navy remains a realistic possibility," he said at an extraordinary meeting of the UN Security Council regarding the situation in Ukraine.

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"Ukraine is ready to settle the situation through political and diplomatic means," the diplomat said.

"The Kremlin's criminal regime has once again demonstrated that it won't stop its aggressive policy and is ready for any acts of aggression against the Ukrainian state," Yelchenko stressed.