Republican senators are expressing alarm over President Trump’s threats to use military force to seize Greenland, warning it could damage NATO and strengthen Russia in its war against Ukraine.

Senators Thom Tillis and Lisa Murkowski plan to travel to Copenhagen to reassure Danish leaders of strong Congressional opposition to any such action.

Murkowski and Senator Jeanne Shaheen are sponsoring a bill to block U.S. funds from being used for military operations against Greenland or any NATO territory.

Senate Majority Leader Mitch McConnell called Trump’s plan “ill-advised” and said it would destroy trust with allies without improving U.S. access to the Arctic, The Hill has reported.

Public support for a Greenland takeover is extremely low, with only 17% of Americans in favor and just 4% supporting the idea by force.