WINNIPEG - The Canadian Wheat Board is asking a judge to overturn federal legislation that would strip the board of its monopoly over western wheat and barley sales.

"The Harper government has reneged on its promise and is now breaking the law, and we intend to hold them to it and ensure that farmers' democratic rights are respected," board chairman Allan Oberg said Wednesday.

The board will file an application with the Manitoba Court of Queen's Bench, asking it to rule Bill C-18 invalid. The bill is currently before the Senate and could become law within weeks, so the board is also asking the court for an injunction to suspend the bill until the case is heard.

The wheat board received support from Liberal Leader Bob Rae, who stood beside Oberg and accused the Conservative government of flouting democracy.

"This legislation takes away an existing right on the part of farmers to decide, together, how they're going to do business," Rae said.

"I think, frankly, our Constitution and our Charter of Rights and Freedoms are all about balancing the rights of Parliament and the rights of others with respect to ensuring that their rights are protected."

The government has already suffered one legal setback over Bill C-18. A Federal Court judge ruled last week that the bill violates the Canadian Wheat Board Act, which says the government must consult farmers via a plebiscite before making major changes.

Justice Douglas Campbell made it clear, however, that his ruling was simply a statement on the government's actions. He did not order the government to halt the bill and said he was not interfering in the legislative process.

Board officials are now taking that ruling to the Court of Queen's Bench in hopes of getting such an order.

The federal government is appealing the Federal Court ruling, and has repeatedly said that Parliament has the right to repeal or amend its own laws.

Agriculture Minister Gerry Ritz said the latest court challenge would not dissuade him.

"Our government will make sure that every farmer has a choice in how they market their grain," Ritz said in a written statement.

"There's a reason the Liberal Party has been completely shut out of rural Western Canada and that's because the Liberal Party doesn't trust western farmers."

The board was set up following the Great Depression to help Prairie farmers band together and seek higher prices. It currently markets about 21 million tonnes of grain to customers in 70 countries.

Supporters say the board's monopoly prevents producers from competing against each other for sales. But opponents say they want the freedom to seek better deals on the open market. They point out that producers of other grains and wheat farmers in other parts of Canada already have that freedom.