Prague Mayor Pavel Bem and Czech Olympic Committee chairman Milan Jirasek signed a declaration of interest to the International Olympic Committee and unveiled the official logo for the capital city's candidacy.

"We are all part of a single national team," Bem said at a ceremony attended by a dozen Czech athletes, including new world track and field champions Roman Sebrle and Barbara Spotakova.

"It's a truly historic moment," Jirasek said. "We're at the beginning of a long journey and we are ready to persevere."

The logo consists of green numbers in the year 2016 shaped like a laurel branch as a symbol of victory.

"All sports fans would be delighted if the Olympics were staged in Prague," said Sebrle, who is also Olympic champion in decathlon.

Candidate cities must submit their initial bid files to the IOC by Sept. 13. Other contenders include Chicago; Tokyo; Rio de Janeiro, Brazil, Madrid, Spain, and Doha, Qatar.

The IOC will select the winning city in 2009.

Prague has never staged the Olympics. The city made an unsuccessful bid for the 1924 games, which took place in Paris.

When Prague's municipal assembly approved the bid in March, Bem acknowledged the city's chances of getting the 2016 Olympics were slim because of geographical reasons. London will be staging the 2012 Olympics, and the IOC is considered unlikely to award the games to a European city twice in a row.