April 19 (Bloomberg) -- Wal-Mart Stores Inc., the world's largest retailer, lost a bid to halt a union at a Canadian store after the country's highest court declined to hear an appeal that would have delayed the process.

The Supreme Court of Canada today refused to hear the Bentonville, Arkansas-based company's appeal of a lower court ruling in Saskatchewan last year that allowed the unionization process to go ahead.

The dismissal paves the way for a ruling by the Saskatchewan Labour Relations Board on whether workers at a Wal-Mart store in Weyburn, Saskatchewan, should be certified so they can bargain for a labor contract. If certified, it would be the third Wal-Mart store in Canada with active union status.

``After losing in the high court, you'd think they have run out of stalling tactics,'' said Michael Forman, spokesman for the United Food and Commercial Workers union, which represents the workers.

Wal-Mart had argued that the labor board should be disqualified from making a decision on whether workers can be represented by a union because it was biased against the company.

Andrew Pelletier, Wal-Mart's Canadian spokesman, didn't return a call.

Second Time

It's the second time that Wal-Mart has lost at the Supreme Court in its effort to stall the Weyburn unionization drive.

The court declined to hear an appeal in April 2005 to overturn the labor board's demand that the company turn over documents to the union. The workers applied for union status in April 2004.

Workers at Wal-Mart stores in Saint-Hyacinthe and Gatineau, both in Quebec, have gained union certification. The company is challenging the Gatineau unionization in court, the union said. The first Canadian store that was unionized, in Jonquiere, Quebec, was closed by the company in April 2005.

Shares of Wal-Mart rose 37 cents to $48.34 at 4 p.m. in composite trading on the New York Stock Exchange.

The case is Wal-Mart Canada Corp. v. Saskatchewan Labour Relations Board, et al. (Sask.), 31813, Supreme Court of Canada.

To contact the reporter on this story: Kevin Bell in Toronto at kbell2@bloomberg.net

Last Updated: April 19, 2007 16:05 EDT