OTTAWA - Billionaire American foundations should not fund Canadian opposition to the Enbridge Northern Gateway oil pipeline project, Natural Resources Minister Joe Oliver says.

"I think it's unfortunate that that kind of financing of Canadian lobbying by foreign interests goes on," Oliver said on Wednesday.

The Northern Gateway would run from the oilsands near Edmonton to a marine terminal in Kitimat, B.C., for Asia-bound tankers.

U.S. tax records show in the last decade, the Gordon & Betty Moore Foundation, Tides Foundation, and others have funnelled $300 million to their Canadian charitable counterparts.

The Canadians then distribute the funding to environmental and aboriginal activists working on projects to block economic development along the northern B.C. coast.

"I am concerned when U.S. interests come into Canada to lobby directly, and sometimes in a hidden way, against Canadian interests," said Oliver. "So, I don't think that's particularly helpful."

The minister says, by contrast, Canadian officials are overt when they go down to the U.S. to lobby American leaders.

Meantime, with more than 4,000 groups and individuals signed up to participate in public consultations on Northern Gateway, the consultation panel says it's final decision will come a year later than planned "around the end of 2013."

Oliver said he still hopes the project will go ahead and keep to its original construction schedule.

"Well, initially the timing was to be 2017," said Oliver. "This may delay it a little bit. We're not sure. We'll see."