Photo shows Canadian Prime Minister Justin Trudeau in brownface

A photo of Canadian Prime Minister Justin Trudeau wearing brownface has emerged a month out from the country's federal election.

The photo was found in a yearbook from West Point Grey Academy in Vancouver, where he used to teach, obtained by Time Magazine. The media outlet says it was taken in 2001 at an Arabian Nights themed gala when Trudeau was a teacher at the school.

In the picture, a 29-year-old Trudeau can clearly be seen wearing brownface as well as a turban and robes. Both his face and hands have been darkened. 

Trudeau addressed the photo on Thursday, saying he "regretted" his actions and "should have known better".

The Liberal Party of Canada - which Trudeau is the leader of - earlier confirmed details of the photo.

"It was a photo taken while he was teaching in Vancouver, at the school's annual dinner which had a costume theme of 'Arabian Nights.' He attended with friends and colleagues dressed as a character from Aladdin," said Zita Astravas, the media relations lead of the Liberal Party of Canada.

Time says it received the yearbook after being given it by a Vancouver businessman who says he wasn't at the gala, but saw the photo in July and thought it should be public.

The timing couldn't be worse for Trudeau, a left-wing, modern politician who will face the Canadian electorate in October. The photo runs counter to Trudeau's attempt at including more people more minority groups in his Government. 

The Prime Minister is also facing questions over whether he pressured his Attorney-General to drop corruption charges against a Canadian engineering firm..

The photo was quickly critcised by the National Council of Canadian Muslims.

Canadian media outlet Fort Murray Today reports that the council's executive director Mustafa Farooq said it the wearing of blackface is "reprehensible".

"The wearing of blackface/brownface is reprehensible, and hearkens back to a history of racism, slavery, and an Orientalist mythology that is unacceptable," he said.

"While we recognize that people can change and evolve over two decades, it is critical that the Prime Minister immediately and unequivocally apologise."