The United States was accused of using Afghanistan as a testing ground for one of its most powerful weapons yesterday.

US forces in Afghanistan dropped a 10,300kg bomb on Isis (Islamic State) forces in eastern Afghanistan yesterday, the Pentagon announced, using the largest non-nuclear bomb ever employed in combat.

General John Nicholson, the commander of US forces in Afghanistan, said the bomb was "the right munition" to use against Isis because of the group's use of roadside bombs, bunkers and tunnels.

The bomb, known as the GBU-43/B, is one of the largest airdropped munitions in the US military's inventory and was almost used during the opening salvos of the Iraq War in 2003. It is also known as a Moab (Massive Ordinance Air Blast) which has earned it the nickname Mother of All Bombs.

Advertisement

By comparison, US aircraft commonly drop bombs that weigh 100kg to 900kg.

However, Hamid Karzai, the former President of Afghanistan, said he "vehemently and in strongest words condemn the dropping of the latest weapon, the largest non-nuclear bomb".

"This is not the war on terror but the inhuman and most brutal misuse of our country as testing ground for new and dangerous weapons," he wrote on Twitter. "It is on us, Afghans, to stop the USA."

US President Donald Trump described the bombing as a "very successful mission".

Afghan officials said the attack on the tunnel complex in Achin district of Nangarhar province left 36 Isis fighters dead.

The US estimates there are 600 to 800 Isis fighters in Afghanistan, mostly in Nangarhar.

There were no civilian casualties, according to a Ministry of Defence statement, which also said that several Isis caves and ammunition caches were destroyed.

Yesterday's blast comes a week after Trump ordered a missile strike against a Syrian regime airport and as tensions rise over North Korea's nuclear weapons programme.

- Agencies

A general view of Achin district, in Jalalabad, after U.S. forces dropped Thursday the bomb, Afghanistan. Photo / AP
A general view of Achin district, in Jalalabad, after U.S. forces dropped Thursday the bomb, Afghanistan. Photo / AP