President Trump said Thursday that Canada is no longer invited to join his international Board of Peace, following days of tension between the president and the United States' northern neighbor.

The president announced the move in a message to Canadian Prime Minister Mark Carney on Truth Social, saying the Board of Peace "is withdrawing its invitation to you regarding Canada's joining, what will be, the most prestigious Board of Leaders ever assembled, at any time."

CBS News has reached out to the White House and Global Affairs Canada for clarification.

The decision came after Mr. Trump formally launched the Board of Peace at an event early Thursday in Davos, Switzerland. The board's official mandate is to help oversee the Gaza Strip under an Israel-Hamas ceasefire deal brokered by the Trump administration last year, though Mr. Trump has hinted at broader ambitions, and exactly how it will operate remains unclear.

Representatives from more than a dozen countries — not including Canada — appeared at a signing ceremony for the board's charter.

Carney told reporters last week that he agreed "in principle" to join the Board of Peace, but he noted that key details on how the board would work and how it would fund Gaza's reconstruction remained unsettled. He also called "unimpeded aid flows" to Gaza a "precondition for moving forward."

His government also ruled out paying to get a seat on the board. A U.S. official previously told CBS News that countries can contribute $1 billion to become permanent members of the Board of Peace rather than having a three-year membership, though payment was not required as a condition of joining. Canadian Finance Minister François-Philippe Champagne told reporters earlier this week that "Canada is not going to pay if we were to join the Board of Peace."

It's not clear why Mr. Trump rescinded Canada's invitation. But the U.S. leader has exchanged harsh words with Carney in recent days, adding to a monthslong dispute between the two neighboring countries over trade and Mr. Trump's tariffs.

In a speech to the World Economic Forum in Davos on Tuesday, Carney warned that the world is "in the midst of a rupture." He pointed to the growing use of "tariffs as leverage," the decline of international institutions and the risk that "[i]f great powers abandon even the pretense of rules and values for the unhindered pursuit of their power and interests, the gains from transactionalism will become harder to replicate."

Carney didn't name-check Mr. Trump, but the speech was widely interpreted in part as a response to Mr. Trump's approach to foreign policy, which has drawn scrutiny in recent days due to his push for the U.S. to take over Greenland.

A day later, in his own speech in Davos, Mr. Trump lashed out at Carney, accusing him of showing ingratitude toward the U.S. despite getting "a lot of freebies from us."

"I watched your prime minister yesterday. He wasn't so grateful. But they should be grateful to us," the president said at one point. "Canada lives because of the United States. Remember that, Mark, the next time you make your statements."

Carney fired back on Thursday, saying: "Canada doesn't live because of the United States. Canada thrives because we are Canadian."

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