TORONTO - Canadian conservation groups have launched an anti-budget campaign condemning federal changes that they say will weaken the country's environmental safeguards.

Organizations including the David Suzuki Foundation, Greenpeace and Equiterre have banded together to oppose what they call a Conservative attack on nature and democracy.

In a series of ads today, they're calling on Canadians to black out their websites on June 4 to voice their disapproval for the omnibus federal budget bill that contains sweeping environmental provisions.

They hope individual Canadians and organizations will alter their websites in ways like making their home pages black.

Rick Smith, executive director for Environmental Defence, says the measures have been "shoehorned" into the budget bill in order to avoid debate.

He says the changes will limit Canadians' ability to engage in the public policy process.

"We're very concerned that the federal government is conducting, essentially, a war on nature and democracy," he says.

Under the new federal plan, the government would have 45 days to decide if an assessment is needed for major economic projects.

If so, the review would take a maximum of two years.

Other changes include recognizing provincial assessments if they meet federal standards.

They would also cut the number of agencies responsible for reviews to three, down from 40.

Natural Resources Minister Joe Oliver has said the new rules will prevent long delays in project approvals that threaten job-creation and hamper the economy.

The groups are also concerned about a crackdown on charities that they say aims to silencing them.

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