U.S. President Donald Trump claimed on Tuesday that Canada is “considering” giving up its citizenship in exchange for protection from the proposed Golden Dome missile defense system at no cost, despite Canadian officials repeatedly stating that the country is not for sale, Fox News reports.

“I told Canada, who really wants to be part of our wonderful Golden Dome system, that it will cost $61 billion if they remain a separate nation, but it will cost zero dollars if they become our beloved 51st state. They are considering the offer,” Trump wrote on Truth Social.

Trump has threatened in recent months to annex Canada, an idea strongly opposed by Canadian officials and their citizens, the Telegraph reports.

Canadian Prime Minister Mark Carney, who secured an election victory last month in part because of Canadian opposition to Trump’s desire to make the country part of the United States, told Trump earlier this month that his country “will not be for sale, ever.”

King Charles III, who is recognized as the sovereign of Canada, gave a speech to the Canadian Parliament on Tuesday in which he appeared to reject Trump’s idea of ​​buying the North American country and making it the 51st U.S. state.

“Canadians can give of themselves far more than any foreign power on any continent can ever take. And that, by adhering to Canadian values, Canada can build new alliances and a new economy that serves all Canadians,” he said.

As for Golden Dome, Trump announced last week that the US had officially selected the architecture for a missile defense system that would create a network of satellites to detect, track and potentially intercept incoming ballistic missiles.

The US president said the project would cost $175 billion to build and was expected to be “fully operational” within three years. He also said Canada would be included in his security net.

“Canada has called us and they want to be part of it. So we’ll talk to them; they want to have protection as well,” Trump said at the time.

Carney’s office said last week that there had been “active discussions” between the US and Canada on current and new security programs, including Golden Dome.

“Canadians gave the prime minister a strong mandate to negotiate a new comprehensive security and economic relationship with the United States,” a spokesman for Carney told the BBC.

“To that end, the prime minister and his ministers are engaging in broad and constructive discussions with their American counterparts. These discussions, of course, include strengthening the North American Space Defense Command and related initiatives, such as Golden Dome,” the spokesman continued.