EDMONTON — A famous TV hoser and several other Canadian actors say they support a protest planned by Greenpeace and other groups in Ottawa against the oilsands industry.

Dave Thomas of SCTV fame says he opposes TransCanada PipeLine's (TSX:TCA.PR.X) proposed $13-billion Keystone XL line that would ship oilsands crude from Alberta to refineries on the U.S. Gulf Coast.

"It is an environmental disaster and an ecological nightmare that must be stopped," Thomas, who is perhaps best known for portraying beer-drinking lout Doug McKenzie on the comedy show, said Tuesday.

"It wouldn't be happening if our country's leaders weren't so deeply vested in the pockets of big business and had even a modest concern for the long-term welfare of their fellow citizens and the planet."

The organizers of Monday's protest, which include the Council of Canadians, Indigenous Environmental Network and the Polaris Institute, hope to muster hundreds of people from across North America in front of the Centennial Flame on Parliament Hill.

They are calling for "a mass act of civil disobedience" to protest the oilsands industry and push for a green energy future that respects aboriginal rights and the health of people and communities.

Other Canadian actors who say they support the planned sit-in include Graham Greene ("Dances with Wolves," "The Green Mile"), Mia Kirshner ("The L Word"), Kate Vernon ("Battlestar Galactica") and Peter Keleghan ("18 to Life"). It is not clear which, if any, of the actors will actually attend the planned demonstration.

Earlier this month, some Hollywood celebrities were arrested in Washington, D.C., in a similar protest against the pipeline, which still must receive final government approval in the U.S.

Supporters of the project say the pipeline would provide the United States with a secure supply of crude oil and spur the creation of badly needed jobs.

Travis Davies of the Canadian Association of Petroleum Producers said the Ottawa demonstration is clearly hoping for the same media attention that the Washington protests received. The industry believes such protesters do not represent mainstream public opinion.

"When you look at what happened in the U.S., over two weeks there were several hundred protesters that got arrested. It was very noisy," he said from Calgary.

"Our polling shows that 85 per cent of Americans believe that U.S. government policy should support the use of oil from Canada's oilsands and 79 per cent of them feel that pipelines are the best way to do that. Clearly this voice, while it has some volume, it is not representative of the way people actually feel."

The XL pipeline would run southeast from Hardisty, Alta., and cross southern Saskatchewan and Manitoba before heading across the border. Different branches of the line would go through parts of Montana, South Dakota, Nebraska, Kansas, Missouri, Illinois and Oklahoma before ending up in Texas.

Thomas said he usually takes a dim view of actors and celebrities speaking out about political issues, but he has had serious misgivings about the oil industry since 1989 when the Exxon Valdez oil tanker ran aground in Alaskan waters, spilling hundreds of thousands of barrels of crude into pristine Prince William Sound.

He worries a breach of the XL pipeline would result in similar environmental havoc.

"I don't believe, typically, that actors should pontificate politically," Thomas said from Los Angeles. "But they are destroying the world and somebody has got to speak up.

"So that's all. I'm speaking up."