MONTREAL - Opposition politicians attending a rally blasting cuts to federal arts spending quickly distanced themselves Wednesday from remarks by one speaker linking Prime Minister Stephen Harper and Nazi dictator Adolf Hitler.

Hundreds of Quebec singers, actors, dancers and writers gathered in a Montreal square to condemn nearly $45 million in funding cuts announced recently by the Conservative government.

The artists accused the government of trying to "censor" artists and running counter to trends in the rest of the world.

But then composer Walter Boudreau delivered a blisteringly sarcastic speech from the stage about the intentions of the federal government and concluded it by shouting, "Heil Hitler."

A couple of people in the crowd also hoisted signs marked with the Second World War-era swastika which branded the Nazis.

Bloc Quebecois Leader Gilles Duceppe, as well as NDP MP Thomas Mulcair and Liberal Denis Coderre were all at the rally and later denounced the gestures.

"These comparisons are totally unacceptable and take credibility away from the very real objections made about these cuts," Mulcair said in a telephone interview.

Coderre said the incident will create a diversion that will be exploited by the Conservatives.

"I can understand the frustration," Coderre said. "But there are limits that must not be crossed."

Duceppe echoed the concerns. He had compared Harper to authoritarian Quebec premier Maurice Duplessis in his speech.

"We must not go too far," he said.

B'nai Brith Canada also criticized the incident, calling for "civilized political discourse as Canadians gear up for what is expected to be a fall election."

"The comparison of Canada's prime minister to Nazi leader Adolf Hitler is obscene and offensive," said Frank Dimant, the group's executive vice-president, in a statement.

"Such statements trivialize the Holocaust and inject ugly rhetoric in what ought to be reasoned debate on real and pressing political issues."

The incident cast a shadow on what had otherwise been a successful rally that drew a number of heavyweights from the Quebec arts scene, including Montreal International Jazz Festival co-founder Andre Menard and noted writer Michel Tremblay.

"We must wonder about the sincerity of a government that recognizes the people of Quebec as a nation when it does not hesitate to cut into the very heart of its existence -- culture," said film producer Denise Robert.

"In addition to ensuring the financial stability of dozens of organizations across Canada, the financial support of government facilitates the collection of private donations which, in turn, can promote production here and abroad," she added. "We attract international investment in culture."

The demonstration was organized by Culture Montreal and the Montreal arts council.

Ottawa announced the cuts during the last few weeks and they include the elimination or reduction of some programs judged crucial by the arts community.