OTTAWA - Canadian Prime Minister Mark Carney and Danish Prime Minister Mette Frederiksen spoke Thursday about strengthening defence ties between their two countries, according to a statement from Carney's office.

"The leaders discussed working together to strengthen collective defence and security, including as close partners in the Arctic and at NATO," it said, noting that both sides looked forward to deepening their relationship and agreed to stay in close contact.

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Both countries are under the threat of US annexation.

US President Donald Trump recently renewed his threat of taking over Greenland, once a Danish colony and now an autonomous territory in Denmark. In an NBC News interview, Trump said he would not "rule it out" making the island a part of the United States.

Meanwhile, Trump reiterated his "51st state" idea as Carney visited the White House on Tuesday, describing the potential integration of Canada into the United States as a "wonderful marriage" and once again labeling the border between the two nations as "artificial".