A News Agency

Trump’s remarks raised the prospect that NATO’s largest and most powerful member could annex the territory of another country, plunging Europe’s decades-old, U.S.-led security alliance into crisis.

Denmark, which is responsible for Greenland’s defense, warned that an attack on Greenland would almost completely spell the end of NATO and announced on Wednesday that it had expanded its military presence “in close cooperation with NATO allies.”

Germany, Sweden, France and Norway confirmed that they would send military personnel to Greenland this week for a joint exercise with Danish forces. Canada and France also said they plan to open consulates in Greenland’s capital, Nuuk, in the coming weeks.

It is not unusual for NATO countries to send troops to other NATO states for training, and allies, including the United States, have for years sought to increase joint exercises in the Arctic Circle. The United States has around 150 troops at Pituffik Space Base in northwestern Greenland.

However, both the timing and symbolism of the European countries’ recent statements amount to an important show of solidarity during an unprecedented period of tension within NATO.