In what is being portrayed as an extremely rare move, former President Barack Obama endorsed Canadian Prime Minister Justin Trudeau in his upcoming election, despite Trudeau admitting to wearing blackface on multiple occasions during his college years. 

In a tweet, the former president called on Canadians to support their prime minister.

"The world needs his progressive leadership now, and I hope our neighbors to the north support him for another term."

Robert Bothwell, a professor of Canadian history and international relations at the University of Toronto, said the last time an American political leader intervened in a Canadian federal election was former U.S. President Theodore Roosevelt more than 100 years ago.

“Trudeau is in real danger,” Bothwell said to the Associated Press. “If I were a Liberal (party) campaigner I would quietly point with pride to Obama’s endorsement. I don’t know if I’d run around toting it as a major political issue.”

Trudeau has faced backlash in recent months after he admitted to wearing blackface during a party he attended as a teacher in 2001, which was the third image that surfaced with him in darkened face makeup. Following that revelation, Trudeau admitted that he could not guarantee that was the last instance of his offensive attire that could be publicized.

“I am wary of being definitive about this because the recent pictures that came out I had not remembered. And I think the question is: ‘How can you not remember that?’” Trudeau said in a news conference in September. “The fact is I didn’t understand how hurtful this is to people who live with discrimination every single day.”

Canadian parliamentary elections are scheduled to be held Monday.