WASHINGTON, January 28. Security guarantees to Kiev would mean the direct involvement of the United States and the West as a whole in a new conflict in Ukraine if one were to start, US Secretary of State and National Security Advisor Marco Rubio said. "But every notion of security guarantees that's been talked about and that the Europeans have pushed is one that requires a strong commitment by the United States as a backstop, which you know, in essence, means we would be committed potentially in a conflict, in a future conflict," Rubio stressed. He repeatedly criticized the military potential of the US's European NATO allies, namely its erosion. US President Donald Trump demands that Europe increase military spending and capabilities, Rubio noted.