Customs officials told the media that three container trucks had crossed through the Chaman land border in southwestern Balochistan province.
Five NATO trucks had been stranded at Chaman due to a blockade imposed by Pakistan and the two remaining vehicles were expected to cross after their contents had been checked by authorities.
On Tuesday, Pakistan ended the blockade of supply lines to Afghanistan after the US apologised for a cross-border NATO air strike that had killed 24 Pakistani soldiers.
The supply routes were shut immediately after the NATO attack on November 26 last year.
Customs officials at the Chaman crossing said they had received orders from federal authorities on Wednesday to allow NATO trucks to pass.
Other officials said hundreds of containers currently at ports in Karachi would soon be shipped to Afghanistan through Chaman and the Landi Kotal crossing in northwest Pakistan.
The blockade forced NATO to send supplies to landlocked Afghanistan through an alternate northern route that is more expensive than the Pakistani supply lines.
The Pakistani Taliban have threatened to attack NATO supply convoys.
Photograph: A truck carrying supplies for NATO troops in Afghanistan crosses into Afghanistan from the Pakistan border town of Chaman.
Credit: Saeed Ali Achakzai/Reuters
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