On Monday, U.S. President Donald Trump threatened that if an agreement to end the war could not be reached “shortly”, the U.S. would carry out widespread destruction of Iran’s energy resources and other critical infrastructure, which could include desalination plants supplying drinking water.

Earlier comments to the Financial Times suggested that U.S. forces might occupy Kharg Island, Iran’s oil export hub. Trump has repeatedly claimed to have made diplomatic progress, despite Tehran’s denial of direct negotiations, whilst stepping up its threats and deploying thousands more US troops to the Middle East.

Legal scholars have stated that the laws of armed conflict permit attacks on civilian infrastructure, such as energy facilities, only where the military advantage outweighs the harm to civilians. This is considered a very high threshold, and causing undue suffering to civilians may constitute a war crime.