The quiet lobbying by Canada's Department of Foreign Affairs and International Trade considers "opposing drilling in the Arctic National Wildlife Refuge" one of Canada's top environmental objectives with Washington, the CanWest News Service reported.

Washington and Ottawa had no immediate comment on the report.

Canada traditionally has opposed drilling in the 19.8-million-acre refuge, the largest protected wilderness in the United States.

Prime Minister Stephen Harper has said little about the issue.

But the news service said documents an Ottawa researcher obtained through Canada's Access to Information Act show the Conservative government lobbied to oppose refuge drilling as recently as this past winter.

On June 18, U.S. President George W. Bush urged Congress to reverse a ban on offshore drilling in the refuge, citing the growing energy crisis.

Besides a belief that the wildlife refuge may have little economically recoverable oil, Canada opposes drilling there because it believes it would likely destroy Porcupine caribou that Gwich'in First Nations and Alaska Native people rely on to live, the news service reported.