The Harper government will hand over the environmental review of certain resource projects to provinces as part of a long-promised overhaul of regulations to be highlighted in Thursday’s budget.

Natural Resources Minister Joe Oliver confirmed Monday that the budget will spell out the government’s intention to reduce regulatory delays faced by energy and mining companies when they propose major projects in Canada.

The package will include legislative amendments that are expected to be part of the government’s overall budget implementation act – a prospect that is raising concerns among opposition MPs and environmentalists that the Conservatives intend to ram through the changes with little debate.

Mr. Oliver said Ottawa is determined to streamline approvals and reduce duplication, and wants to reach deals with individual provinces that would see only one level of government conduct an environmental assessment of a major resource project.

“And that doesn’t mean that the province will necessarily be the one to step back; it could be the federal government if the province has the capacity to do the review,” Mr. Oliver said in an interview. “And a number of the provinces do, in fact, have that capacity.

The Conservatives have been signalling for months that they intend to reduce the hurdles that resource companies face, whether in the oil sands, in constructing pipelines or in building mines. However, the changes will not affect the current hearings on the Northern Gateway pipeline, the proposal by Enbridge Inc. to ship oil-sands bitumen to Kitimat, B.C., for export by supertanker to Asian markets.

Opposition parties and environmental groups are clearly bracing for a fight, saying the government is weakening its regulatory oversight to accommodate the wishes of major oil and mining companies.

New Democratic Party MP Megan Leslie said the government isn’t interested in reforming the system to make it more manageable, but is rather intent on gutting it.

“When they say streamlining, it means dismantling, full stop,” Ms. Leslie said in an interview. “There are ways to make things more efficient that doesn’t mean tearing apart the assessment system that we have.”

As the government’s main defender of the oil sands, Mr. Oliver was in Toronto on Monday, touting the benefits of the oil sands and other resource developments for Ontario manufacturers and insisting the country needs to modernize its regulatory system to attract investment..

In the interview, Mr. Oliver said the regulatory changes will be highlighted in the budget “to demonstrate the importance the government is giving to this initiative and the timeliness of it.”

“In other words, we want to get on with it as quickly as we can,” he said.

He would not reveal details of the plan, and said the budget will contain only a few specifics.

In his speech, he said the resource development and environmental protection are not mutually exclusive.

“I am confident that we can achieve a regulatory system that protects Canadians and the environment and at the same time supports Canada’s competitive advantage,” he said.

The minister has already said the reviews conducted by the National Energy Board and the Canadian Environmental Assessment Agency should have strict time limits, rather than stretch on for as much as six years, as was the case with Total SA’s Joslyn oil-sands mine that was approved last December. At the time, the minister said a review should take no more than two years.

The government will also raise the threshold of projects to be reviewed and is expected to introduce changes to the Fisheries and Oceans Act that would reduce the protections for fish habitats from industrial development.

Executives from the oil and mining industries have been lobbying aggressively to have Ottawa overhaul its approach to environmental review, saying the process is needlessly bureaucratic and duplicative.

Pierre Gratton, president of the Mining Association of Canada, said his members are particularly keen to see Ottawa and the provinces agree to one jurisdiction conducting the environmental review, rather that repeating the effort at each level.