SHANGHAI (AFP) -- China plans to spend nearly half a trillion dollars on ambitious plans to expand its road and railway networks in the coming years, state media said.

The government is to invest two trillion yuan (250 billion dollars) in expressways in the next 30 years and 1.5 trillion yuan (190 billion dollars) in railways within just four years, according to state press.

The plans were unveiled at a time when the nation's transport infrastructure regularly shows signs of being stretched to the limit by a population of 1.3 billion increasingly mobile people.

To counter the problem, the government will build 85,000 kilometers (53,000 miles) of expressway in the next three decades, Xinhua news agency reported, citing the Ministry of Communications, or transportation ministry.

At the same time, China plans its largest ever railway expansion, boosting its rail service capacity by 20 percent, the China Daily said, quoting Li Guoyang, an official with the National Development and Reform Commission.