In an article at Asia Times Online, Syed Fazl-e-Haider writes about co-operation between China and Pakistan, including plans to extend the Khyber Pass line and build the Spin Boldak line. There is also discussion of a direct China – Pakistan railway.

Chinese shun Pakistan exodus

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China has also shown interest in early laying a track between the Pakistan border town of Torkham and Jalalabad in Afghanistan, as the Chinese want to use the Pakistan Railways network to transport their goods and equipment for the development of copper mines and various other projects in Afghanistan. Separately, Pakistan Railways has completed a feasibility study for a rail section between Chaman, in Balochistan, and Kandahar in Afghanistan that is part of a proposed link across Afghanistan to Turkmenistan.
Source: Asia Times Online, 2009-09-11