GT: Some critics argue high-speed rail is a waste of resources. Is that true?

Sun: We should admit the necessity of developing railways in China. Rail is the main artery of the national economy, a popular means of transport, and plays an important role in improving people's livelihood.

However, when proceeding railway construction, the proportion of various train services should be carefully handled.

High speed rail mostly serves a small group who are not sensitive to ticket prices. Large-scale construction of high-speed rails not necessarily feasible in China. The value of time is directly proportional to the net income level of a country. Our bullet trains are the fastest in the world, but income levels don't even break the top hundred globally.

What we should do is to make an overall railway development plan. We need to develop high-speed rail, but at the same time we should upgrade the existing lines and promote the development of various other fast trains.

The current plan is to finish 16,000 kilometers high-speed rail by 2020, I am not advocating slowing down the construction speed, but the key point is that we should optimize the investment in railway, and more importantly, provide the people with a varied rail network.

GT: China's bullet trains are the fastest in the world, but some Western countries question their safety. Is this fair?

Sun: Questioning our bullet trains' safety is understandable. We have only developed bullet trains for six years, but are aiming at the same level as developed countries. Leapfrog development has some problems. The upgrade of the bullet train's speed should be based on a mass of experiment data, a sufficient safety factor and a long period of testing.

There's some risk involved with bullet trains at the moment. The highest experimental speed of the Shanghai-Hangzhou high-speed railway is 416.6 kilometers per hour (kph), and the real running speed is as 350 kph. The gap between the two speeds is too small.

We only reached the speed of 350 kph with our trains on August 1, 2008. I think we'd better take more time to consolidate the speed. Although upgrading speed has great significance for technological progress and innovation and China is eager to win world recognition and improve international competitiveness, we need to be more cautious.