Opposition to Canada's oil sands will only intensify unless Ottawa takes strong action on climate change, said a Canadian official cited by local media Wednesday.

"The oil sands are an issue in themselves, but just as much a proxy for the bigger agenda of 'off oil,'" Marc LePage, a special adviser on climate change and energy issues at the Canadian embassy in Washington, said in an email to Ambassador Gary Doer.

LePage warned that the anti-oil sands campaign in the United States is part of a larger battle against the fossil fuel industry and "will likely intensify in the absence of (Canadian) movement on climate change legislation."

The document was obtained through an access to information request by PostMedia News.

Canada signed on to curbing greenhouse gas emissions in 1992 but successive governments have delayed action to regulate or cap industrial pollution.

Opposition to the oil sands manifested itself recently in protests in Washington and Ottawa against a proposed pipeline which would run from the tar sands in the Canadian province of Alberta to the Gulf of Mexico in the southern United States.

Washington has launched consultations on the 1,700-mile (2,700-kilometer) Keystone XL pipeline, which would pass through the US states of Montana, South Dakota, Nebraska, Kansas and Oklahoma before ending up at refineries in Texas.

The final decision on whether to press ahead with the project is expected within weeks.

Environmental groups have called on US President Barack Obama to deny a permit for the $7 billion dollar project, which is part of a broader $13 billion TransCanada pipeline system.