That's according to French Foreign Minister Jean-Yves Le Drian, Ukrinform reports, citing Bloomberg.
"Any violation of the border, any intrusion would lead to extremely grave consequences," Le Drian said in an interview with French radio RTL.
According to the report, in the past few weeks, the United States warned its European allies that Russia may be planning a repeat of its 2014 invasion of Ukraine, citing a fresh build-up of tanks and troops along the border.
At the same time, according to Le Drian, it is important to find a "way to work together," even though President Vladimir Putin's "authoritarian" tendencies have become more marked in recent months.
In addition, he said that Russia should instead bring its influence to help resolve the deepening crisis in Belarus. "Now is the time for Russia to exert pressure [on Belarus]," Le Drian said, adding that Alexander Lukashenko risks creating a humanitarian disaster.
Kyrylo Budanov, head of the Main Intelligence Directorate of the Ministry of Defense of Ukraine, said earlier that Russia had amassed more than 92,000 troops along Ukraine's borders and is preparing for an attack by the end of January or beginning of February.
Secretary of the National Security and Defense Council Oleksiy Danilov, in turn, said that Russia, by building up its troops near Ukraine, is trying to raise the stakes ahead of upcoming talks.