US defense contractors are on shaky ground just a month into the new administration — taking a backseat to European peers — as mounting concerns over a deluge of policies including a tightened military spending budget send shock waves across the government-sensitive group.

Political and military leaders in Europe are fleshing out details of a plan for Ukraine once the guns fall silent.

France and Estonia will host a meeting of European defense ministers on Monday to discuss how to bolster support for Ukraine, according to people familiar with the matter.

The Kremlin said on Thursday that any plan to send European troops to Ukraine as part of a potential peacekeeping mission would be unacceptable for Russia and that it was monitoring such proposals with concern.