The Chinese government is planning to expand the country's high-speed rail network to 30,000 kilometers (18,600 miles) by 2020, part of public infrastructure spending aimed at shoring up economic growth.

Vice Transport Minister Yang Yudong said Thursday the network would connect more than 80 percent of China's major cities.

Yang says China plans to invest 3.5 trillion yuan ($504 billion) in railway construction between this year and 2020.

He was speaking at a briefing introducing a government white paper outlining plans to improve the country's transportation services.

The plans call for the renovation of expressways and faster construction of railways to serve less-developed regions in central and western China.

Official statistics show China's high-speed railway totaled 19,000 kilometers (11,800 miles) last year.