Canada's top court has decided not to hear a bid by Wal-Mart to challenge the Saskatchewan Labour Relations Board over a union effort to organize company stores in the province.

Wal-Mart was seeking leave to appeal a November decision by the Saskatchewan Court of Appeal, whichbacked a lower court ruling that said the members of the board were not biased against the company.

But the Supreme Court of Canada said Thursday that it would not hear the company appeal. As usual, it gave no reasons for the decision.

That leaves the Saskatchewan appeal court decision in place. On Nov. 15 last year, it ruled that "there is no evidence of a reasonable apprehension of bias" at the board.

While Wal-Mart was challengingtheboard's fairness, the boardheard an application to certify United Food and Commercial Workers, Local 1400, atWal-Mart's Weyburn store. The board has not made a decision yet.

An application for the North Battleford store has been adjourned.

Wal-Mart has been fighting efforts to certify unions at a number of its Canadian stores.