REGINA - The federal Liberals say Prime Minister Stephen Harper is insulting Canada's legal system by insisting he will continue to fight for an end to the Canadian Wheat Board's monopoly on barley sales.

"Stephen Harper, prime minister or not, is not above the law,'' agriculture critic Wayne Easter said Tuesday in a release.

Late last month, a Federal Court judge stopped a move by the  Conservative government to end the monopoly. The judge said the   federal cabinet overstepped its authority and can't make that decision without approval from Parliament.

Harper has since insisted he won't change direction and vowed last week that the government will bring about the change "one way or another.''

He repeated the assertion Monday night to supporters in Lloydminster, Sask., where he said "this battle isn't over.''

The appropriate response to a court ruling is that a prime minister will work "in accordance with the law,'' said Easter.

"The answer that Stephen Harper gave was that he and his government will continue their effort to undermine the board, regardless of the ruling of the court.''

Harper has said the battle isn't a personal decision, but rather based on the will of farmers. A majority of producers who voted opted for dual-marketing of barley in a government-run plebiscite last spring.

He has not said how the government plans to move the issue forward or whether it will appeal the court's ruling.