Röttgen supported the European Union leaders' decision to impose sanctions on 21 individuals after the referendum in Crimea that paved the way for Putin to annex the region from Ukraine. By August 2014, he demanded that Europe respond to the escalation of violence in Ukraine by agreeing to further sanctions against Russia, saying that "[a]ny hesitation would be seen by [Russian President Vladimir] Putin as European weakness that would encourage him to keep going." However, he ruled out a U.S. proposal to arm Ukraine against Russia, calling it a "grave mistake" which "not only would [give] Putin a pretext to expand the war beyond eastern Ukraine, it would also serve his other goal to divide the West wherever he can."