President Donald Trump cited potential Canadian taxes on U.S. tech companies as his reason for ending trade talks with Canada on Friday.

The president posted on Truth Social that Canada had planned to put a tax on U.S. technology companies, calling the move "a blatant attack."

Trump’s decision is the latest blow to an already strained relationship between the bordering nations. Trump has said the U.S. should annex Canada to improve trade relations and security. Recently elected Canadian Prime Minister Mark Carney has staked his political reputation on pushing back. He has said Canada isn’t for sale.