Sen. Lisa Murkowski (R-Alaska) joined with a Danish lawmaker on Monday to push back against President Trump’s continued insistence that U.S. control of Greenland is necessary for American national security.

Murkowski, who has publicly disagreed with Trump in the past, and Aaja Chemnitz, who represents Greenland in Danish Parliament, said in the joint statement that Americans should work to view Greenland as a partner, not as a potential asset.

“As legislators representing Greenland in Denmark and the United States, we see a better path forward,” the two lawmakers wrote in the statement.

“The United States, like Denmark, should recognize that the future will be defined by partnership, not ownership,” they continued. “To ensure our alliance reaches its full potential, Americans must view Greenland as an ally, not an asset. Open for business, but not for sale.”

Murkowski and Chemnitz said they understand why Trump, as a businessman, would be interested in acquiring Greenland, but they said the issue has been settled.

“The appeal of Greenland is easy to understand,” they wrote. “It is strategically located for defense, shipping, and more. It is also a storehouse for all sorts of minerals, the building blocks of society that will determine who leads—and controls—the industries of the future.”

“Of course, a businessman turned president would be interested. But Greenland is not for sale. The question has been asked and firmly answered by the government of Greenland, Naalakkersuisut,” they continued.

Trump has focused intently on plans to take over Greenland, a semi-autonomous Arctic island that is part of the kingdom of Denmark. During his inauguration speech, Trump referred to the U.S. as a growing nation expanding its territory. He has also called for the U.S. to retake the Panama Canal and mused about annexing Canada. 

Trump and Denmark Prime Minister Mette Frederiksen spoke on Jan. 15 in what was reportedly a 45-minute “fiery” phone call. According to the Financial Times, senior European officials said the conversation spiraled into confrontation, and that Trump, who was president-elect at the time, was aggressive and threatened tariffs against the NATO ally. 

The Danish prime minister said at the time she referred to remarks by the chair of Greenland’s Parliament that the island is not for sale and that it is up to Greenland to make its decision about its independence. 

National Security Council spokesperson Brian Hughes did not comment on the tone of the call but said Trump is focused on Greenland as part of the larger competition between China and Russia. 

“President Trump has been clear that the safety and security of Greenland is important to the United States as China and Russia make significant investments throughout the Arctic region,” Hughes said in a statement.

“The President is committed to not only protecting U.S. interests in the Arctic but also working with Greenland to ensure mutual prosperity for both nations,” he added.