Abu Dhabi and London (CNN)A lot has happened since Gulf Arab states downgraded ties with Iran in January 2016 when an angry mob stormed the Saudi embassy in Tehran and set fire to it following the Saudi execution of a prominent Shiite cleric.
Iran's nuclear agreement with world powers came into effect that month, but the Trump administration withdrew from it just two years later, leading to a wave of tit-for-tat
attacks that affected oil and shipping in the Persian Gulf.