The Arms Trade Treaty (ATT) official becomes international law on Wednesday, which establishes for the first time global rules to stop the flow of weapons and munitions to countries where they could be used to commit serious human rights violations.
However, it does nothing about the hundreds of millions of guns already in circulation worldwide.
At Peshawar's Karkhano Market, for instance, anyone can find antique Enfields used by British troops in World War I, Soviet AK-47s from the 1980s, and M-16s stolen from NATO warehouses in Afghanistan.
Experts fear that many of these weapons wind up in the hands of Taliban fighters.
Al Jazeera's Kamal Hyder reports from Peshawar, Pakistan.
Source: Al Jazeera