China is aiming to build separate passenger and freight networks within its railway system, one of the world's busiest. It may come true on some bustling lines in 2015, when a high-speed passenger transport network is expected to become fully operational. According to a five-year plan on China's transport system recently approved by the State Council, China's cabinet, China will create a high-speed railway backbone network featuring four east-west lines and four north-south lines by the end of 2015. The Ministry of Railways told China's (Xinhua) News Agency that the total milage of high-speed railway will reach some 18,000 km by then. Railway expert Wang Mengshu said that as new high-speed lines open, transportation capacity will be released from conventional lines, which will gradually turn into freight lines. World Bank figures show that China has by traffic volume the world's second business freight railway and the busiest passenger railway. Wang noted that China had only 93,000 km of railways by the end of 2011. "The railway mileage per capita is shorter than the length of a cigarette." "The railway density in China is far from adequate to serve the world's second-largest economy," he said.