The 21st century's first World Exposition opened in Japan with governments and companies showcasing technology and culture in a six-month event expected to draw 15 million visitors.

Humanoid robots walked, danced and played music alongside real humans who carried flags of 121 countries on a stage in Japan's industrial heartland of Aichi some 250 kilometers (155 miles) west of Tokyo.

"I hope this exposition will become the starting point for us to think about coexistence of humans and nature," Prime Minister Junichiro Koizumi told more than 2,000 invited guests at the forest park, which will open to the general public Friday.

"The key to make environmental protection compatible with economic development is technology. By managing to promote both environmental protection and economic prosperity, we must pass on this beautiful Earth to our children," Koizumi said.

The theme of the latest Expo, which traces its roots to the 1851 Great Exhibition in London, is "Nature's Wisdom" with 121 countries hosting displays meant to show the link between technology and the environment.

The six-month event is expected to draw some 15 million people with exhibits on everything from advanced robots to a frozen mammoth dug up in Siberia, with the host country hoping to regain its image as a world innovator.

Heads of state or government, including French President Jacques Chirac, Australian Prime Minister John Howard and Central American leaders, are due to visit the fair to promote their countries.

The event has been dubbed the "Toyota Expo" as it takes place in the base of the automaker, which is Japan's largest company and will entertain guests at its pavilion with robots performing everything from a brass ensemble to hip-hop.

Japan readied for the Expo by opening last month its third international airport, Centrair, as a gateway.

Flags of the participating countries and four international organizations were carried in a march on the Expo Dome main stage of the venue to the sounds of a symphony orchestra comprised of musicians from around the world.

Japanese modern dancers and traditional actors of Noh plays performed for the ceremony, while children acted out skits with a message to protect the environment.

It is the first World Exposition to take place in Japan since 1970 in Osaka.

That exhibition is credited with solidifying the image of post-World War II Japan as a technology powerhouse, six years after the Tokyo Olympics confirmed Japan was back on the map as a major world player.

"The World Exposition is the mirror that shows the shape of the era," said Shoichiro Toyoda, chairman of the world fair.

"We have a mission to display modern civilizations and culture as well as the latest technologies and pass them on to make the future generations prosperous," he said.

In a parallel, the next World Expo will be held in 2010 in Shanghai, two years after Beijing hosts the summer Olympics in a sign of China's rise.

Japan had watched its neighbor's ascent as an economic power warily and hopes the World Expo will highlight the more modern theme of eco-friendly technology.

(China Daily March 25, 2005)