NEW YORK - General Motors, battling to keep its global sales crown, fell further behind Toyota during the second quarter as a deteriorating U.S. market overshadowed gains overseas.

U.S. sales for GM fell 21 percent during the April-June period, while Toyota's dropped 7.8 percent. The U.S. has been a drain on both automakers as record gasoline prices curb demand for larger vehicles, such as GM's Chevrolet Tahoe and the Toyota Tundra pickup.

GM said in June that it plans to close four plants that make pickups and SUVs by 2010. It may sell its Hummer SUV division.

Toyota will suspend production of Tundra pickups and Sequoia large SUVs for three months beginning Aug. 8 at its factories in San Antonio and Princeton, Ind. Tundra assembly will then be consolidated in Texas. The company also said Wednesday that it will make the Prius hybrid car at a new plant in Mississippi starting in late 2010 to meet surging demand, changing its initial plan to build the Highlander SUV at the factory. GM closed at $14.62, up 30 cents in New York Stock Exchange composite trading. Toyota's American depositary receipts fell 95 cents to $91.92.