Famine has killed at least 105m people since 1870, according to research conducted by the World Peace Foundation. The vast majority were victims of political decisions and acts of war rather than drought. But by the turn of the millennium such man-made disaster had diminished to the extent that experts in the field, such as the UK academic and writer Alex de Waal, felt mass starvation might be a thing of the past.

This year that progress has dramatically reversed. The renewed use of starvation as a weapon of war is threatening millions of lives in Nigeria, South Sudan, Somalia and Yemen. The situation in Yemen is the most catastrophic.

The conflict there descended into a new circle of hell after Saudi Arabia committed its air force to defeating Houthi rebels in March 2015. In the process, roads, bridges and markets have been destroyed, the container docks at the port of al-Hudaida were bombed, and other infrastructure ruined. At Riyadh’s insistence and with the backing of Britain and the US, the UN Security Council imposed a blockade on the country.