US fears worst scenario of Russia against Ukraine

"I’m very concerned about the situation near Mariupol. I think that we should take care of the eposecurity architecture to protect Ukraine, its border, buffer zone, etc.," Kaptur said.

"This is what Ukrainian President Petro Poroshenko should ask at [his] most important meetings with the representatives of different countries," she said.

"Poroshenko should not lose any opportunity to talk about it, to involve the presidents of other countries," Kaptur said.

"We should protect Ukrainian border and any city by all means. Kharkiv and Mariupol are now very vulnerable. And we do not know about what the Russian military strategists are thinking now," she said.