U.S. fearing that Pakistan could cut off the main means of providing American and NATO forces with fuel, food and equipment.

Citing unnamed Pentagon officials, the newspaper said that in 2009, the US had moved 90% of its military surface cargo through Karachi and then through mountain passes into Afghanistan.
Now almost 40% of surface cargo arrives in Afghanistan from the north, along a patchwork of Central Asian rail and road routes that the Pentagon calls the Northern Distribution Network, the report said.
The US military is expanding its Central Asian supply routes to the war in Afghanistan, fearing that routes going through Pakistan could be endangered by deteriorating US-Pakistani relations, The Washington Post reported.

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