The Saudi-led coalition fighting Houthi rebels in Yemen has commenced court martial proceedings against air crew in relation to breaches of international humanitarian law, in the first such case of its kind.

“The coalition affirms its commitment to rules and provisions of international humanitarian law and holds violators of IHL, if there be any, accountable in accordance with the regulations of each coalition state,” a coalition spokesman said at a news briefing in London.

The case relates to the conduct of three airstrikes. The first was an attack on a hospital supported by the French health charity Médicins Sans Frontières on 15 August 2016. Sixteen people died, according to MSF. At the time the Saudi coalition said an error had occurred, but MSF said coordinates for the Abs hospital had been given to the coalition five days prior to the attack.

The second was a strike on a wedding ceremony in Bani Qayis in April 2018 that left 20 dead and many more injured. The Saudis initially defended the strike, which used a US missile, saying it believed a foreign ballistic expert was present with a well known Houthi leader.

Subsequently the coalition’s joint incident action team found that an error had occurred breaching rules of engagement, and recommended some form of punitive action.

The third incident was a strike in August 2018 on a civilian bus in Dahyan that left more than 40 schoolchildren dead, most of them aged under 10.

The JIAT claims to have conducted 182 investigations of specific incidents, and found breaches of rules in 22 cases.

Immediately after the third attack the official Saudi press agency called the strike a “legitimate military action” which targeted those who were responsible for a rebel missile attack on the Saudi Arabian city of Jizan a few days earlier. The British government called for a transparent investigation.

Although the admissions, and reports of judicial action, represent a change of policy stance by the Saudis, Riyadh’s critics will point to the length of time such investigations are taking and will await reports of actual punitive action against named officers. Compensation to some of the victims of the incidents has already been made.

The admissions will be taken as proof by campaigners that they were right to demand an end to UK arms sales to Saudi Arabia on the grounds that the kingdom was breaching international humanitarian law in its Yemen air campaign. The news comes as Saudi coalition forces insisted they were still willing to continue backdoor talks with Houthi military officials about finding an end to the five-year civil war in which the Houthis would be given a role in a future government.

The Saudis had thought talks with the Houthis mainly conducted through tribal mediators were making progress after the Houthi leadership called a truce. Saudi analysts believed the Houthis were persuaded into talks because they had come to realise that Iran, the Houthi’s sponsor, was putting its interests ahead of the Houthis as part of an attempt to bog Saudi Arabia down into an expensive and unwinnable war.

In recent months the Houthis have stepped up lethal military attacks in a sometimes successful bid to gain grounds in areas such as Marib.

Saudi sources also said UN agencies would meet in Brussels on Thursday to discuss how humanitarian aid could continue to be supplied in the face of Houthi disruption of supplies and the imposition of a 2.5% tax on all aid in Houthi-controlled areas. The US, one of the largest donors supplying aid, has said a suspension would start on 1 March.

The United Nations provides food assistance to more than 12 million people a month in Yemen, which was very poor even before the conflict erupted. Fighting, reduced commerce and economic upheaval have all contributed to widespread hunger and disease.

Aid agencies say Houthis continually seek to determine the recipients of UN food aid in regions under its control as part of a strategy of reinforcing its political authority.