President Donald Trump has repeatedly said Canada should be the 51st U.S. state, effectively erasing the massive border the two nations share.

CNN’s chief White House correspondent was drowned out by laughter from her colleagues in the Oval Office on Thursday after her line of questioning about Russia’s war in Ukraine prompted President Trump to tear into her and the network.

President Trump said Thursday that Canada is a “serious contender” to become the 51st state, alleging that America’s neighbor to the north needs US “protection.” Trump, 78, has repeatedly floated the idea of Canada joining the Union — even mockingly referring to outgoing Prime Minister Justin Trudeau as “governor” — and revisited the topic while signing a memorandum ordering reciprocal tariffs on countries around the world.