Canada has recommended taking humpback whales off the “threatened” species list, two months before the government is due to decide whether to approve a proposed pipeline that would lead to half a million barrels of oil being shipped through their Pacific marine habitat every year.

The Department of the Environment released a document over the Easter holiday that recommends the North Pacific humpback whales should now be labeled a “species of special concern.”

The change of classification means the humpback’s habitat would no longer be protected under Canada’s Species at Risk Act, thereby removing some of the risk of legal battles with environmental groups that could scupper Enbridge Inc’s controversial Northern Gateway pipeline project.

“It’s a very cynical political move that is not based in science, designed solely to permit the Enbridge Northern Gateway pipeline to be approved by removing the designation of critical habitat for the whales,” said Karen Wristen, executive director of marine conservation group Living Oceans Society.

The recommendation stems from a 2011 study that found the whale population had increased since it was first listed under Canada’s Species at Risk Act in 2005. It is now in the hands of the Governor in Council, which can amend the legislation after a 30-day response period.

The government’s document does not draw a connection between the Northern Gateway project and its recommendation on humpbacks.

Northern Gateway would carry crude from Alberta’s oil sands to the northern British Columbia town of Kitimat for loading on tankers that would sail through the Douglas Channel, a breeding and feeding ground for humpback whales.

As a threatened species, the humpback’s critical habitat was legally protected, leaving the door open for court challenges around the potential impact of development on those waterways.

Under the new classification, the whales and their habitats would not be legally protected by the Species at Risk Act, although developers would still need to mitigate potential dangers such as whales colliding with tankers, oil spills and shipping noise.

The company has promised to take safety measures including reducing speeds of tankers to lower the probability of collisions and using remote detection and monitoring of whale populations.

An Enbridge spokesman declined to comment on the matter on Tuesday.

A federal review panel has recommended approval of the project if Enbridge can meet 209 conditions, including measures centered around marine mammal management. The Conservative government has strongly supported the plan, though it has said it would only approve pipelines that are safe for people and the environment.

The decision to change the status of humpback whales prompted ire from Canada’s official opposition, the New Democratic Party (NDP), which accused the government of overriding public concerns “to please their friends in the oil industry.”

Mélanie Carkner, a spokeswoman for Fisheries and Oceans Canada, said humpback whales and their habitats would still be protected by the Fisheries Act and Marine Mammal Regulations.

She said the government was committed to working with Canadians to protect at risk species.

While humpback populations have made a comeback in recent years, environmental groups are concerned that increased shipping in the Douglas Channel could threaten them.

“Their recovery isn’t complete and we still need to be working to protect them the best way we can,” said Linda Nowlan, regional director, B.C. and Pacific, for World Wildlife Fund Canada.

“It’s kind of ironic that the best form of protection is being removed at a time when the threats are increasing.”