Three experts working for the UN's top human rights body say the governments of Yemen, the United Arab Emirates and Saudi Arabia may have been responsible for war crimes including rape, torture, disappearances and "deprivation of the right to life" during three-and-a-half years of escalated fighting against rebels in Yemen.

In their first report for the Human Rights Council, the experts also point to possible crimes by rebel Shiite militia in Yemen, who have been fighting the Saudi-led coalition and Yemen's government in a civil war since March 2015.