Earlier this year, Chinia's fastest operational locomotive was able to cover the 824-mile trip between Beijing and Shanghai in five hours maintaining an average speed of 165mph and reaching a record-breaking top speed of 200mph.

That record looke like it will be short lived as CSR Corp, China's state-owned train maker, has now unveiled a prototype train capable of reaching speeds up to 310 miles (500 kilometres) an hour. The latest test model has a maximum tractive power of 22,800 kilowatts, compared with 9,600 kilowatts for the Beijing-Shanghai CRH380 trains.

China has built the world's largest high-speed rail system in less than 10 years with 8,000 miles of track at a cost of 700 billion yuan (£66billion). Another 8,000 miles of line is expected to be added by 2015. A collision between two high-speed trains in July that killed at least 40 people led it to suspend new projects. (see our story “Safety review after Chinese high speed rail crash” Wednesday, 27 July 2011)

The new experimental train was unveiled in the eastern province of Shandong by CSR Corp, according to the China Daily newspaper.

The train, whose sleek design was inspired by an ancient Chinese sword, was built using plastic reinforced with carbon fibre and magnesium alloy to reduce weight and so increase speed according to the report but there was no indication of when the six-car train would be put into commercial use.

China's bullet trains routinely travelled at around 300 kilometres an hour, but the government reduced speeds after the July accident, which involved trains made by CSR.

Initial reports suggested signalling problems were to blame for the crash, which lead to strong public criticism of China's government, but the results of an official investigation have not yet been published.

Another new high-speed railway which links Guangzhou (the capital of the southern province of Guangdong) to Shenzhen city on the border with Hong Kong went into service on Monday, the official Xinhua news agency reported.

China plans to extend the route to Hong Kong by 2015 as part of the planned Beijing-Hong Kong high-speed line.

The latest moves come despite China saying it will cut spending on its railways next year.

The railways ministry will invest 400 billion yuan (£40 billion) on rail infrastructure in 2012, down from an estimated 469 billion yuan this year and 700 billion yuan in 2010.