The Committee on Arms Export Controls (CAEC) reconvened for the first time in almost two years on Wednesday in response to the chorus of international condemnation against Britain for supplying Saudi Arabia with arms that are being used to target civilians, an international humanitarian crime. CAEC heard evidence from Saferworld, Amnesty, Human Rights Watch (HRW) and Oxfam, who have published documentary evidence on individual cases of the Royal Saudi Air Force bombing Yemini hospitals, ports, warehouses, factories, schools, markets and homes.

Their message was clear, unanimous and withering: the UK is breaking its own laws and fuelling a humanitarian catastrophe by selling arms to Saudi Arabia. British law is also clear: it is illegal to sell arms to a state that is at a “clear risk” of committing international humanitarian crimes. But over the past year alone, Britain has sold around £6bn worth of weapons to Saudi Arabia, whose campaign in Yemen is targeting civilians – 191 such attacks have collectively been reported by the UN, HRW and Amnesty.

Saudi Arabia’s intervention has precipitated the world’s worst humanitarian and development crisis: 82% of Yemen’s population of 24 million people need aid, 60% need food and 10% have fled their homes. Last week Médecins Sans Frontières (MSF) reported that it had received scores of dead and wounded from a Saudi strike on a busy market. MSF has seen three of its facilities targeted in as many months. Weddings have been hit. So too have homes for the blind. A water bottling factory was struck with cruise missiles, killing dozens of workers, whose bodies melted into the machinery. The list goes on.

In his evidence to the CAEC (itself made up of the committees from the departments of international development, business, defence and foreign affairs) David Mepham, the UK director of Human Rights Watch, implied the foreign secretary, Philip Hammond, had lied in his defence of Britain’s arms sales to Saudi Arabia when he said last month that Britain has found “no evidence of breaches of international humanitarian law”. Mepham said he had personally handed him HRW’s documentary evidence, complete with GPS coordinates of Saudi air strikes on schools, hospitals and markets. He added that the government “has had that evidence for months, and therefore it is extraordinary the line can come back that they do not have the evidence, when that evidence has been shared with them for a considerable period of time”.

Another witness, Amnesty International’s arms expert Oliver Sprague, questioned the honesty or the competence of the government, which when questioned over allegations of Saudi international humanitarian crimes in Yemen said: “The use of UK supplied weaponry in the conflict in Yemen is an operational matter for the Royal Saudi Air Force.”

“That’s fundamentally incorrect,” Sprague said. “The entire purpose of our export control regime is to link responsibility of the exporter to the eventual use of their weapons … If they say this is not a matter for us, it is impossible to authorise that weapon lawfully.”

The only refutation of the testimony from the rights groups was from CAEC member Daniel Kawczynski, who dismissed their field research because he knew that no violations of international humanitarian law had occurred – the head of the Royal Saudi Air Force had told him so.

On the fundamental issue being examined by the CAEC of Britain’s complicity in Saudi war crimes, this is an open-and-shut case. The government knows what it is doing but it dresses it up in the language of “supporting the legitimate government in Yemen”, when Yemen has not had a proper election in 10 years. It also flatly rejects the contention that billions of pounds of illegal arms sales to Saudi Arabia play a role in inflaming the human disaster in Yemen.

The government views the humanitarian and human rights disaster as a secondary consideration to the money private British arms companies make off the war. That the government affords Department for International Development (DFID) no role in the decision-making process on to which countries the UK sells arms is telling.

To fund the reconstruction of the civilian infrastructure in Yemen, largely destroyed by the Saudis with our weapons, the United Nations has asked international donors such as DFID for £1.8bn, which approximates to the profits the UK arms industry has made off Saudi’s intervention in Yemen. We must escape the cycle of selling arms to dubious regimes to sow destruction and then using the taxes on those arms sales to finance an aid budget to clean up the mess. To stop this cycle the government needs to do nothing more than obey the law.