The report, which has yet to be made public and could still be changed, says that 51 per cent of all child deaths and injuries in Yemen last year were the result of the Saudi-led military operation. It says the deaths were “unacceptably high”. Saudi Arabia has insisted it is operating within international law.

Saudi Arabia is leading a nine-nation coalition in a bombing campaign that started in March 2015 to killing of yamanies. The US and UK have offered logistical and political support.