Environmental activist David Suzuki was among a group of Canadians in Washington, D.C., today to urge U.S. President Barack Obama's administration to reject the Keystone XL pipeline, telling Americans that Canadian Prime Minister Stephen Harper can’t be trusted when it comes to climate change promises.

Members of the group were in a panel discussion sponsored by the Natural Resources Defense Council and titled “What happened to Canada?”

Delegation members met Thursday and were also meeting Friday with members of Congress and representatives from the State Department. They voiced opposition to TransCanada's proposed pipeline, which would link Alberta's oilsands to refineries in Texas but is still under review by the U.S. government.

The panelists said they are trying to inform Americans that dissent when it comes to Harper’s environmental policies isn’t allowed north of their border with Canada, and that Canadians haven't been allowed a real debate about the expansion of the Alberta oilsands, which they referred to as the tarsands.

They gave the “muzzling” of federal government scientists as an example of how Harper is trying to prevent an informed debate about climate change and the environmental impacts of pipelines.

“This government has systematically been suppressing the ability of our scientists to speak up,” Suzuki said. “Government scientists, paid by our tax dollars, are not allowed to speak to the press without first being vetted through the Prime Minister’s Office.”

A 'critical crisis' for Canada

Canadians aren't getting the scientific-based evidence they need to make big decisions, Suzuki said. “This is, I think, a critical crisis for Canada.”

In an interview after the talk, Suzuki said the government's claim that Canada is leading the world in fighting climate change can't be taken seriously, based on how it has undervalued the importance of science. He said Americans should know what's going on in Canada, particularly because of the steady stream of Harper cabinet members who visit Washington and advocate for the pipeline to be approved.

"Americans think of Canada as a country of fair play and they listen to our leaders with respect, and when our leaders come down and tell them stories, stories based on a total absence of science to support what they’re saying, I think it’s important that America understand the limit of what our so-called leaders are telling them,” he said.

Author and activist Tzeporah Berman said on the panel that she lives in a country she no longer recognizes. She said Harper has made a string of broken promises when it comes to climate change, and Americans shouldn't believe him when he or his ministers come to Washington and say development of the oilsands will be carried out in an environmentally friendly way.

“We’re arguing that Obama needs to refuse the Keystone XL pipeline both for America's own interest, and because our government cannot be trusted when it promises it will be a responsible project and will address the impacts of climate change,” she said.

While the small team of Canadians is trying to get its anti-Keystone message across in the U.S. capitol, Obama is hearing from some far more influential Americans. The CEOs of dozens of major companies, the U.S. Chamber of Commerce and the National Association of Manufacturers sent a letter Oct. 9 asking the president to approve TransCanada's project.

They said the pipeline is important to the fragile American recovery, and will affect investor confidence and American competitiveness.

"We know your Administration is carefully considering the environmental risks associated with Keystone XL, as it should. Those risks, like those incumbent in many other significant projects, must — and can — be managed, through appropriate regulation and careful stewardship," the letter stated.

Natural Resources Minister Joe Oliver said he was pleased to see American business leaders stand up for a project that will create jobs and energy security for both countries.

Oliver advocates for Keystone approval

"I have no comment on U.S. internal political matters. However, we believe that if the relevant facts are taken into consideration, the project will be approved on its merits," Oliver said in an email response.

Oliver said the U.S. needs to import an increasing amount of oil and that Canada is a "secure, environmentally responsible friend and neighbour."

At a news conference in Vancouver, Oliver was asked to what extent the ongoing U.S. government shutdown might be delaying the review.

He said he wouldn't comment on an internal American political matter, but that, "We continue to believe that if all the facts and science are considered, this project will ultimately be approved."

Oliver said people with different opinions have every right to express them, but that a lot of rhetoric is "unrelated to reality."

"We're sticking to the facts and we have a very strong story to tell," he said.

Canadian artist Franke James was also part of the panel in Washington, and her poster creations related to the oil industry and the environment are going up around city streets, in bus shelters and other spots.

"Canada is sacrificing democratic and human rights for oil industry profits," she said.