Construction of the US pavilion at the 2010 Shanghai World Expo started in Shanghai at 10:00 a.m. Friday.

Visiting US Commerce Secretary Gary Locke and Ma Xiuhong, Chinese vice minister of commerce, and Yang Xiong, vice mayor of Shanghai attended the ground-breaking ceremony.

"The Haibao doll that sits in my office is looking forward to reports on your progress - as are the rest of us back in Washington," said a congratulations letter from US Secretary of State Hillary Clinton to the event.

"The United States is proud to participate, and President Obama and I are committed to doing everything we can to support your work," said Clinton in the letter read by Jose H. Villarreal, the US Commissioner General to the 2010 World Expo, at the ceremony.

The United States was the 240th country (organization) to confirm participation in the 2010 World Expo Shanghai and the 212nd country (organization) to sign the participation contract on July 11, according to the Shanghai World Expo Bureau.

Zhou Jun, an official of the International Exhibition Division of Shanghai World Expo Bureau, said the global economic slowdown had effects on the fund-raising of the U.S Pavilion since late 2008, which made the country a late comer to confirm its participation to the expo.

"US laws make it clear that the government can't participate in the World Expo with federal budget," he said.