Justin Trudeau has refused to rule out the existence of more pictures of himself in blackface as he said white "privilege" had blinded him to the racism of the practice.

Three separate cases of Mr Trudeau wearing blackface have emerged in the last two days, shredding his reputation as a liberal poster boy a month before the Canadian elections.

During a press conference on Thursday afternoon, Mr Trudeau said he "deeply regretted" the incidents, saying it was the sort of discrimination ethnic minorities "face on a regular basis". "I didn't see that from the layers of privilege that I have. And for that I am deeply sorry, and I apologise".

He declined to be drawn on whether further photographs may emerge, saying "I am wary of being definitive about this because the recent pictures that came out I had not remembered."

Mr Trudeau admitted he did not reveal the episodes to his Liberal Party during vetting processes when he ran for office, saying "I never talked about this. Quite frankly I was embarrassed".

The Canadian leader's political turmoil began on Wednesday night, when Time magazine published a yearbook photograph of a 29-year-old Mr Trudeau wearing robes and a turban, his hands, face and neck coated with brown makeup.