Afghan President Hamid Karzai has banned the sale and possession of ammonium nitrate fertiliser, which is used by Islamist insurgents to make deadly homemade bombs, a statement said Friday.
"Import, production, possession, use, purchase and sale of ammonium nitrate fertiliser is banned," the president's decree said.
The substance is intended for agricultural use and widely available, but it is a key ingredient in improvised explosive devices (IEDs), the Taliban weapon of choice in the worsening insurgency.
"Based on investigations by security forces, terrorists widely use the fertiliser in making explosives. To avoid such terrorist actions any use of this substance will (result in) judicial prosecution," the statement said.
The militants waging a bloody insurgency against the Afghan government and international forces use widely available materials to make deadly suicide vests, car bombs and roadside bombs.
The decree said anyone in possession of the fertiliser must hand it over to branches of the Ministry of Agriculture within one month.
The interior and finance ministries will train police and customs employees to detect, recognise and seize the chemical, while the National Security Council will oversee the implementation of the decree.
Militants also use ball bearings, nuts and bolts, pressure cookers, batteries and electric wires and use cheap mobile phones to remotely detonate the bombs.
The Taliban have used IEDs to devastating effect -- they are the biggest killer of foreign troops in Afghanistan.
Experts say IEDs are cheap and easy to put together. Rigged to timers or remote controls, they can be detonated when vehicles drive over pressure plates or are linked into a chain of bombs to cause maximum damage.