NEW YORK - Burger King Holdings Inc expects lower third-quarter revenue and restaurant margins in the U.S. and Canada as bad weather in the central and eastern United States kept diners away.

The fast-food chain operator said on Tuesday over 75 percent of its U.S. and Canada segment's restaurants are located in those regions and said the segment's comparable-system sales fell 8.2 percent in January and February from a year earlier.

On Monday, Archrival McDonald's Corp reported a better-than-expected 4.8 percent rise in February sales at established restaurants as Asia helped offset softness in the United States and Europe.

Earlier on Tuesday, restaurant operator Ruby Tuesday Inc also forecast a decline in same-restaurant sales at company-owned locations in the third quarter due to bad weather.

Burger King estimated the weather reduced January and February U.S. and Canada system comparable sales by about 3 percentage points.

Burger King, maker of the Whopper sandwich, said worldwide comparable sales for the two-month period ended February 28, 2010 were down 5.4 percent, helped by overseas sales.

Burger King shares were down 2.6 percent at $17.85 in pre-market trading.

(Reporting by Dhanya Skariachan, editing by Gerald E. McCormick and Derek Caney)