He says significant Russian forces remain at Ukraine's border.
U.S. Secretary of State Antony Blinken says Russia has the capacity to take aggressive action against Ukraine if it so chooses.
He announced this at a joint press conference with Ukrainian President Volodymyr Zelensky in Kyiv on May 6, 2021, according to an UNIAN correspondent.
"Russia has pulled back some forces, but significant forces remain at Ukraine's border. It has pulled back some equipment, but significant equipment remains near Ukraine's border. And so Russia has the capacity on fairly short notice to take aggressive action if it so chooses, and so we are watching this very, very carefully," he said.
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He praised the way Ukraine had been handling Russia's provocative actions.
"I must tell you that I admire the restraint that Ukraine has shown in the face of these provocative actions, in the face of this aggression," he said. "Ukrainians continue to lose their lives on a regular basis, and yet the restraint is very, very real and very much appreciated. Ukraine has not taken to the provocations by Russia."
According to him, the United States, many allies and partners are focused on such issues.
"This is the subject of extensive discussion at the most recent NATO meetings, and as well at the meetings of the G7 just in the last two days. In turn, we are, as I said, actively looking at strengthening even further our security cooperation and our security assistance to Ukraine. Nothing to announce today, but it's something that we're very actively looking at," he said.
The sides also discussed the Minsk negotiation process and diplomatic efforts to resolve the conflict. "We also discussed the diplomacy, the Minsk process and commitments that were made, and we'll always continue to explore ways to see if there are opportunities to help advance the diplomacy. But there again, Russia continues to be the recalcitrant party in not engaging in good faith in trying to resolve the – both Crimea, of course, and the Donbas, and restoring what is rightfully Ukraine's, which is its border and its territorial integrity and sovereignty over its – over all of Ukraine," he said.