The Ministry of Railways would delay a plan to speed up trains for the sixth time by October 2005 for technical reasons, Minister of Railways Liu Zhijun said Wednesday.

The timetable for the planned speed increase remained undecided, said the minister.

The speed increase was impossible for 2005, said Liu, who said the year was "a preparation year" for the increase.

"Compared with the fifth speed increase in April 2004, the sixth is more complicated and difficult," Liu said.

He said the ministry needed to upgrade more than 840 kilometers of lines and many communication signals before the speed increase.

After it raises the speed for the sixth time, China will have more than 22,000 kilometers of railways designed for speeds above 120 kilometers per hour.

Of the total, 5,300 kilometers will have a speed of 200 kilometers per hour, including the lines linking Beijing and Shanghai, Beijing and Harbin and Lanzhou and Lianyungang.

China will invest 100 billion yuan (US$12 billion) on railway construction in 2005, almost double the investment in 2004, said Liu Zhijun.

Editor: Catherine