Canadian Prime Minister Justin Trudeau apologized on Thursday after it emerged that he had worn racist makeup on at least three occasions decades ago. But he declined to rule out the possibility that more images could emerge.

"I am wary of being definitive about this, because the recent pictures that came out I had not remembered," Trudeau said.

Trudeau was speaking in the Canadian city of Winnipeg in an attempt to head off the scandal that threatens to hurt him and his Liberal Party's chances in the upcoming Canadian elections, scheduled for late October.

The controversy emerged after Time Magazine published a photo on Wednesday evening of Trudeau wearing brown makeup to an "Arabian Nights" themed party at a private school in 2001. At the time, Trudeau, the son of a former Canadian prime minister, was 29 years old and a teacher.

Trudeau apologized shortly after the photo was made public and said he now believes the photograph is racist, though he said he did not believe it was racist at the time.

Following the publication of Time's story, Trudeau revealed that he had also worn blackface once in high school during a performance of "Day-O," the Jamaican folk song popularized by American singer and civil rights activist Harry Belafonte.