TOKYO -- Inspectors from the International Olympic Committee (IOC) ended their tour of Tokyo on Sunday, praising the Japanese capital's "highly professional" bid for the 2016 Summer Games.

In the face of the global economic downturn, which has hit Japan particularly hard in recent months, the Tokyo bid has strived to emphasize its sound financial health.

This includes a $3.7-billion reserve for construction of venues and infrastructure and financial guarantees from the government for what organizers say will be the most compact and environmentally friendly Olympics ever.

"We have been most impressed to find what Tokyo could offer the Olympic Games," said Nawal El Moutawakel, chairwoman of the IOC evaluation commission, at the end of four days of briefings and site visits.

At a news conference, she thanked the Tokyo bid committee "for the excellent and highly professional preparation, cooperation, hard work and hospitality.

"We are very impressed by the vision, the high quality of presentation and the concept that was presented to us," she said, but added the IOC would need to further study the bids by Tokyo and the three other candidates.

The IOC commission has already visited Chicago and will tour Rio de Janeiro and Madrid in the coming weeks. It will draw up a report a month before around 100 IOC members choose the 2016 host on October 2.

Tokyo is the only one of the candidates to have hosted the Summer Games before, in 1964, an event which helped it become an economic superpower.

For 2016, Tokyo plans to concentrate 95 percent of the venues within eight kilometers (five miles) of a 100,000-seat main stadium to be built on a landfill.

Around 70 percent of the venues will be within a 10-minute ride of the athletes' village.

On the theme of environmental protection, the stadium will be partly covered by a canopy of solar power cells, while the equestrian, rowing, and cycling venues will be set on a forested islet built on heaps of garbage.

El Moutawakel, an IOC executive board member, called Tokyo a "dynamic city," but had noted during her visit to Chicago that there were "four strong bidders" for 2016.

Tokyo governor Shintaro Ishihara said, "We managed to answer very pointed questions. I think they could understand the superb vision and concept of Tokyo's bid."

"We have been given assurances regarding financial aspects, which we are going to study carefully," said El Moutawakel, a Moroccan who won the inaugural women's 400-meter hurdles at the 1984 Los Angeles Olympics.

"We have also witnessed the support of the business community," she said.

The number of Japanese big business firms that support the Tokyo bid, including airlines and sportswear makers, has increased by six to 13 in the past week.

Financial issues have been a major concern among IOC leaders, including president Jacques Rogge, because of the world recession.

"Although the financial situation is a little bit difficult, I don't think this situation will last forever," El Moutawakel said.

"You never know if other crises might happen. But we are happy to see four of the strongest cities bidding for the Games."

Chicago has United States President Barack Obama among its supporters and London was helped by then-premier Tony Blair when it won the right to host the 2012 Summer Games.

Japanese Prime Minister Taro Aso has met the IOC commission twice -- at a welcoming ceremony and a dinner at the Akasaka Palace state guest house -- and pledged his government's full support for Tokyo's bid.

"We were pleased to meet the prime minister, himself an Olympian," said El Moutawakel.

Aso competed in clay pigeon shooting at the 1976 Montreal Olympics.