“Russia should not invade the sovereignty Ukraine,” she stated to CBS News chief foreign affairs correspondent Margaret Brennan, “Face the Nation” moderator. “We are cooperating with our allies and have made it clear that we are ready to issue sanctions like never before.

In an interview with Brennan Monday, the vice president declined to comment on whether new sanctions would directly target Putin. “I don’t want to talk about specific sanctions. But we are making it clear to him. And we are having direct conversations.”

The U.S. believes that Putin has not yet made a decision to invade Ukraine despite the massive Russian military presence at the border. Concerns about an invasion are rooted in the 2014 annexation by Russia of Crimea. This is considered a violation of Ukraine’s sovereignty and has not been recognized by international communities.

Putin is against NATO expansion eastward in his sphere, and he doesn’t want Ukraine to become NATO member. Ukraine has accepted Europe and wants to be a part of the NATO alliance.

For Ukraine, there is currently a State Department level 4 “do not fly” travel advisory. COVID-19 was the reason not to travel in an earlier advisory. However, the latest advisory, which was issued Monday, mentions Russia’s military threat.

The advisory states that “U.S. citizens ought to be aware of reports suggesting Russia is planning significant military action against Ukraine.” This is the highest advisory from the department. It warns of “greater risk of life-threatening threats” and creates an environment that could make a U.S. government unable to assist any traveler in crisis during an emergency.

In April, the Biden administration sanctioned Russia for a different reason: to retaliate against incursions such as the SolarWinds cyber spy campaign and Moscow’s interference with the 2020 presidential election.