Natural Resources Minister Joe Oliver defended the government's use of an omnibus budget bill to pass changes to environmental regulations, arguing he has spoken to Canadians about it and the opposition can put knowledgeable MPs on the committee studying it.

The 400-page bill contains major changes to environment policy, as well as budgetary measures and other changes.

The finance committee studies budgetary measures. Oliver says a subcommittee will look at the environmental changes in C-38, the budget implementation bill.

"The study will be a public exchange with witnesses from every side of the debate," he said.

"The membership of the committee will be set by each party’s whip to ensure that relevant critics can study these important changes."

The government has faced criticism over putting so many different changes into a budget bill, particularly from environment groups.

Conservatives critical of environmental advocacy groups

Oliver has referred to some environmental advocacy groups as radical. Last week, Environment Minister Peter Kent accused some environment groups of money laundering, although he wouldn't name any of the ones he had in mind.

"Essentially what our government is doing through the finance committee is investigating allegations that offshore funds have improperly been funnelled through — laundered if you will, that's a fairly accurate word — through Canadian organizations that have charitable status to be used in ways that would be improper given that charitable status," Kent told Evan Solomon, host of CBC's Power & Politics, on Tuesday.

Pressed whether the use of the word "laundering" suggests criminal activity, Kent said: "There are allegations — and we have very strong suspicions — that some funds have come into the country improperly to obstruct, not to assist, in the environmental assessment process," Kent said.

The environmental review process is intended to determine whether a project poses adverse environment effects and whether those effects can be mitigated.

Money laundering is a crime where the proceeds of illegal activity are concealed or converted to look like they came from a legitimate source.

Imagine Canada, an umbrella group that represents charities, has demanded Kent name the charities or retract the comments.

Asked for his view, Oliver said, "I haven't used that term and I don’t think people were being accused of criminal activity."