London, December 12 (RHC)-- Saudi Arabia used British-made cruise missiles during an attack on a civilian Yemeni factory, say Amnesty International and Human Rights Watch.

According to a report published by the human rights groups, remains of PGM-500 missiles, manufactured by the UK firm Marconi Dynamics, were found in the rubble of a factory that was targeted near the capital Sanaa in September.

"The attack on the factory in the Sanaa governorate, which appeared to be producing only civilian goods, killed one person, and was in apparent violation of international humanitarian law," read a Human Rights Watch statement.

Earlier, British Foreign Minster Philip Hammond announced that weapons exports to Saudi Arabia would be halted if investigations prove that Riyadh is breaching international humanitarian law during its ongoing aggression against Yemen.

"The latest revelations show UK policy to be both misleading and seriously ineffective. Despite multiple, well-documented cases of violations of the laws of war by the Persian Gulf coalition in Yemen, UK ministers have consistently refused to acknowledge this," said UK Director at Human Rights Watch David Mepham.

Based on a 2013 British parliamentary report, the UK had granted some four billion pounds worth of weapons export licenses in the five years leading to the report.