China raised the maximum speed of its popular Beijing-Shanghai bullet trains up to 350 kph Tuesday, following years of restrictions amid safety concerns.

Axar.az reports citing Sputnik that, China's Fuxings have once again become the world's fastest trains with the journey between Beijing and Shanghai being reduced from 5 hours and 45 minutes to 4 hours and 28 minutes.

The fact that the train connects the Chinese capital in the north with the country's most important trade megalopolis in the south makes it one of the most popular means of transportation among Chinese residents.

According to Huang Xin, a representative of China Railway Corporation (CR), tickets for the journey are sold weeks in advance.

"These trains are so popular that the tickets for today's services sold out a week ago," Xin said Thursday, cited by Xinhuanet.

Fuxings are the latest "China Standard" bullet trains, completely designed and manufactured in China, capable of running at 350-400 kilometers per hour.

However, for several years their speed remained capped at a mere 300 kilometers following a nationwide chorus of safety concerns amid the 2011 Wenzhou bullet train crash that killed 40 and injured around 200.