Metropolitan Expressway has opened the 47-km-long Central Circular Route encircling central Tokyo.

The expressway is expected to ease traffic congestion in the region, while improving access to Haneda Airport.

Called Route C2, the Central Circular Route serves the central part of the Greater Tokyo Area and involved construction costs of JPY2tn ($16bn).

"We hope to make Tokyo the world’s number one city, as we are preparing to host the Olympics and Paralympics in 2020."

Construction on underground sections of the route began in 1992.

The Central Circular Route connects Kasai junction in Edogawa Ward and Oi junction in Shinagawa Ward and its new section stretches for about 9.4km between Ohashi junction in Meguro Ward and Oi junction.

Tokyo Governor Yoichi Masuzoe told The Japan Times: "The completion of the Central Circular Route is expected to bring a variety of benefits.

"We hope to make Tokyo the world’s number one city, as we are preparing to host the Olympics and Paralympics in 2020."

Completion of the expressway is expected to shorten car travel time between Shinjuku and Haneda airport to 20 minutes from about 40 minutes.

Traffic jams on metropolitan routes inside the Central Circular Route will also be cut down by about 40%.

Tokyo’s other two circular routes include the Tokyo-Gaikan Expressway (Outer Ring Road) and the Metropolitan Intercity Expressway.