BEIJING - Blacktop highway will reach all counties in Tibet during the 12th Five-Year Program period (2011-2015), said Li Shenglin, China's transport minister, during the ongoing parliamentary session.

Li said the central government would significantly increase investment to improve transportation in Tibet during next five years, at least doubling the investment during the 11th Five-Year period, without specifying the figure.

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By the end of 2015, most of villages in Tibet will be accessible by highways, he said.

At present, tarred roads have reached 80 percent of counties and 80 percent of villages have been linked by highways.

Tibet is going to have highways totaling 70,000 kilometers long by the end of 2015, almost 20 percent up from the current 58,000 kilometers, according to the transport authority of Tibet autonomous region.

Further, Li said, the central government would support Tibet in building an expressway network, or "4-hour economic zone", linking five major cities, Lhasa, Xigaze, Nagqu, Shannan and Nyingchi with expressways.

When the network completes, Xigaze, Nagqu, Shannan and Nyingchi could be reached within four hours' drive from Lhasa.

At present Lhasa-Nagqu section has been completed, and Lhasa-Xigaze section will be completed this year, and distance between Lhasa and Shannan is also likely to be shortened to 4-hour's drive this year.