If Trump walks away, or if Kyiv rejects a deal and keeps fighting with European support, it won’t necessarily mean “the collapse of Ukraine” although more people will almost certainly die if the U.S. pulls its air defenses and intelligence-sharing capabilities, Heisbourg said.

The European union is preparing a "plan B" on how to keep economic sanctions against Russia should the Trump administration abandon Ukraine peace talks and seek rapprochement with Moscow, EU's high representative for foreign and security policy,