The Chamman crossing was closed after a mob of Afghan youth celebrating the country's national day on August 18 ransacked the border gate and burnt a Pakistani flag, paramilitary official Safdar Khan said.
Chamman in the south-western Pakistani province of Balochistan is one of the two border crossings through which supplies to NATO troops are transported after they arrive at Pakistani seaports.
Hundreds of lorries carrying foodstuffs and other goods were parked on both sides as Pakistani and Afghan officials held meetings over the weekend to resolve the issue, Khan added. No agreement was reached.
The commanders are scheduled to meet again on Monday to sort out the matter, he said.
Tensions between Pakistani and Afghan forces have resulted in the closure of border crossings in recent months, causing difficulties for commuters and traders and halting NATO supplies.
Torkham, the other major crossing, remained closed for weeks earlier this year when troops from both countries clashed over a border gate Pakistan had planned to build.