NATO Secretary-General Jens Stoltenberg has expressed "unwavering" support for Ukraine from the Alliance, AP reported.

“NATO stands with Ukraine,” Stoltenberg said during a news conference with Ukrainian Foreign Minister Dmytro Kuleba, calling the Russian movements “unjustified, unexplained and deeply concerning.”

“Russia has moved thousands of combat troops to Ukraine’s borders, the largest massing of Russian troops since the illegal annexation of Crimea in 2014. Over the last days, several Ukrainian soldiers have been killed in eastern Ukraine,” he said.

Ukraine's foreign minister said that if Moscow takes any reckless steps or starts a new spiral of violence, it will be costly in every sense.