SINGAPORE — Singapore — due to host tens of thousands of foreign visitors for its first Formula One Grand Prix this weekend — said Tuesday it is unlikely to meet its annual target for tourist arrivals.

Visitor arrivals in August fell 7.7 percent compared with a year earlier, to 842,000, the Singapore Tourism Board said.

It was the third straight month in which visitor arrivals fell, a reflection of “the current challenging global economic environment and outlook for the tourism sector, which may continue into 2009,” the board said.

After more than four years of gains, tourist arrivals began declining in June.

“While the tourism sector is likely to fall short of this year’s target of 10.8 million visitors, the Singapore Tourism Board is strengthening its efforts in increasing tourism (spending) to achieve the tourism receipts target of 15.5 billion Singapore dollars (11 billion US),” it said.

Officials have estimated 40,000 overseas visitors will be in the crowd for Sunday’s Formula One Grand Prix race through the city-state’s streets.

The race will be the sport’s first held at night and should generate 100 million Singapore dollars annually in revenues, officials have estimated.

Tourism officials have been working with the private sector to offer a series of events surrounding the race. These range from free cultural shows and concerts, to a river festival, a motor show, and high-brow affairs including the Amber Lounge after-race party, which costs 1,000 Singapore dollars to get into.

The Tourism Board said Indonesia, China and Australia led tourist arrivals in August, but nine of the top 15 markets saw a decline, likely because of a global economic slowdown.

Along with the Grand Prix, the tiny but affluent city-state is trying to boost its appeal by building new attractions including two casino developments which are expected to open by 2010.

Singapore is also trying to become an arts and entertainment centre, and will host the inaugural Youth Olympics in 2010.