The federal budget dealt a massive blow to the environmental movement and will result in protests across the country, two opposition MPs say.

The latest federal budget unveiled by Finance Minister Jim Flaherty set out limits for environmental reviews that could speed up approval for projects such as the Northern Gateway pipeline.

Flaherty called the current system where some reviews have been underway for six or seven years "nonsense" and said they're slowing down or threatening the Canadian economy.

But British Columbia MPs Elizabeth May, leader of the Green Party, and the NDP's Nathan Cullen call the budget undemocratic and its stance on the environment the worst in Canada's history.

"I can't imagine another time in our nation's history when a significant threat facing our economy, our kids, like the climate crisis, would not even merit a mention," May said on CTV's Question Period Sunday.

"(It's) a budget that throws everything at fossil fuel extraction, while demonizing the environmental movement, threatening it and killing the advisory body that tells you about the crisis . . . it's got to merit the worst Canadian budget in our history," she said.

Cullen said never before in Canada's past has the full weight of a government been used to override the will of citizens.

"I don't know if it's just pure cynicism on the prime minister's part, or a lack of intelligence about how British Columbia works, but trying to change the rules midway through, if he's expecting that we here on the West Coast are simply going to shrug our shoulders and turn away and allow him to build a pipeline that threatens our very way of life, he's got another thing coming," he said.

He called the government's proposed "one project, one review," process an "extraordinary" policy that attempts to thwart public debate and opposition.

Cullen said it will hurt the Canadian economy in the long run when projects go wrong and taxpayers are stuck paying for an environmental mess.

He also said First Nations will not be bullied by the government into accepting a project like Northern Gateway - a pipeline that would link the oilsands with the West Coast to export oil to Asian markets - without a fight.

"We've seen this movie before and they'll be joined by many allies right across the country, I can guarantee you that," Cullen said.

May said public opinion in B.C. is "dead-set" against the pipeline and having oil tankers on the province's coast - opposition that crosses party lines.

"Particularly in waters Environment Canada itself has said are the fourth-most treacherous waters on the planet . . . this is not like the East Coast, this is distinctly different," she said.

"It's a shocking anti-nature budget but it's also anti-democratic," May said, adding environmental organizations themselves are concerned their funding or charitable status will be cut if they're overly critical of economic projects supported by the Conservative government.

Cullen said leaner regulations and controls to protect the environment only serve to damage Canada's reputation.

"It makes a laughing stock of all of the rules and regulations in Canada and again on the international stage, could Canada be punching itself in the face any harder? It's embarrassing," he said.

Pipelines are expected to be on the agenda Monday as Prime Minister Stephen Harper meets with U.S. President Barack Obama and Mexico President Felipe Calderon for a summit in Washington.

Obama, facing an election this year, has taken a cautious approach to the proposed Keystone XL pipeline that would ship Canadian oil to refineries on the U.S. Gulf coast.

Canada has been pushing hard for approval of the overall project.

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