WASHINGTON, Sept 25, 2007 (AFP) - US authorities Tuesday approved six new flights between the United States and China, including two ahead of the upcoming Olympic Games, under a civil aviation deal signed earlier this year.

The boost comes amid growing demand for travel between the two countries and as Beijing gears up for the 2008 Summer Olympics.

The Department of Transportation said it made a final decision to award Delta Airlines a new direct route from Atlanta to Shanghai, making the carrier the first to fly that route, and approved a United Airlines direct route from San Francisco to Guangzhou.

"Delta's new flights to China will fill a critical void in air travel today by providing the 65 million residents of the Southeast (US) with direct access to the world's fastest-growing economy," the carrier's chief executive Richard Anderson said.

Delta said its flights would start March 30, 2008.

United Airlines chairman and chief executive Glenn Tilton said the carrier "is honored to be selected as the first US carrier to provide nonstop service between San Francisco and Guangzhou, important cities in the world economy." The United flights will begin in the first half of 2008.

The US agency also announced tentative approval for four new daily flights to begin in 2009: American Airlines for Chicago-Beijing service; Continental Airlines for Newark-Shanghai service; Northwest Airlines for Detroit-Shanghai service; and US Airways for Philadelphia-Beijing service.

Final decisions on these routes will be made after public comment periods.

The announcement followed a hotly contested decision for a single route in 2007, awarded to United Airlines for a Washington-Beijing route, based on the earlier civil aviation agreement.

After that decision, the two governments signed a deal to vastly expand the number of flights allowed in recognition of growing economic and business links.

"By bringing China and the US one step closer, we increase our ability to compete, boost our success in the global marketplace, and make international travel for all passengers easier and more affordable," Transportation Secretary Mary Peters said in a statement.

The new US-China civil aviation agreement signed May 23 will more than double passenger flights between the two countries by 2012 and greatly expand air cargo flights.

Under the old agreement, US airlines today could operate only 10 daily flights into Beijing, Shanghai and Guangzhou.

Continental said that if its plans win final appoval it would begin service in March 2009 between the New York-area Newark airport and Shanghai, with a connection to Cleveland, Ohio.

"This is a win for Continental's customers, co-workers, and each of these communities," said Larry Kellner, Continental's chairman and chief executive officer.

The US Airways flight from Philadelphia to Beijing would originate at the airline's hub in Charlotte, North Carolina, starting in 2009, the carrier said.

Northwest said its flights were tentatively set to begin March 25, 2009.

"This is a great development for travelers who need convenient nonstop service between the US and China," said Northwest CEO Doug Steenland.