NDP Leader Tom Mulcair condemned Republican presidential front-runner Donald Trump as a "fascist" and criticized Prime Minister Justin Trudeau for not denouncing the billionaire business mogul.

"Donald Trump is a fascist. Let's not kid ourselves, let's not beat around the bush," Mulcair said in a question-and-answer session after a speech to party staff last Tuesday.

A video clip of Mulcair's toughly worded remarks surfaced Thursday, just over a week before he faces a leadership vote at his party's convention in Edmonton.

CBC News requested and received the video clip from Mulcair's office after it first appeared on BuzzFeed News, which reported that it had obtained the video from the NDP. The 38-second clip has been edited, and does not include the question Mulcair is answering. The leader himself tweeted other clips from the event to his followers last week.

"I will not hesitate to point out the fact that Mr. Trudeau just shrugs his shoulders when he's asked about Donald Trump and says, 'Oh the relationship between Canada and the United States goes beyond any two individuals.' I'm sorry, if a fascist becomes president of the United States, I want to be on record as having opposed it long before that election," Mulcair says in the clip.

Mulcair pointed to Trump's policy proposal to ban non-U.S. Muslims from entering the country and build a wall along the Mexican border as proof of what he called fascist tendencies.

Trudeau won't 'pick fight' with Trump

Trudeau has been asked to assess Trump's meteoric rise — and enduring popularity despite his off-colour and offensive remarks  but has repeatedly demurred.

"I'm not going to pick a fight with Donald Trump right now. I'm not going to support him either, obviously," Trudeau said during a recent town hall meeting.

In a separate interview with Rosemary Barton on CBC News Network's Power & Politics, Trudeau was asked why he wouldn't "speak more forcefully" against Trump. "Anti-Muslim rhetoric, anti-woman rhetoric, building walls against people — why don't you say what you actually think about him?" Barton asked Trudeau. 

Trudeau asked about Donald Trumps's campaign for the Republican nomination0:41

"I respect the American electoral process. I have faith in what [Abraham] Lincoln referred to as 'the better angels of American nature,' and I am looking forward to who I am going to work with after Nov. 4," Trudeau said in the interview at the end of his official visit to Washington earlier this month.

Leadership review looms for Mulcair

Mulcair, who will be the subject of a leadership review vote at the party's convention April 8-10, also stridently denounced the Liberal government's budget last week, painting his party as a progressive bulwark against Liberal austerity.

The NDP leader has faced criticism from a number of party members for his performance in the last election campaign, but others in his parliamentary caucus — and prominent union leaders — have lined up behind him in advance of the vote.

A leadership election could be triggered if 50 per cent plus one delegate at the convention supports such a move.