Tensions between Iran and the West have escalated since U.S. sanctions on Iranian oil exports took full effect and British naval forces seized an Iranian supertanker.
Below is a timeline of recent incidents:
May 2 - The United States, which withdrew from an international nuclear accord between Iran and global powers in 2018, ends waivers that had allowed some mainly Asian importers to continue buying Iranian crude
May 5 - The United States says it is deploying an aircraft carrier strike group and bombers to the Middle East, citing threats from Iran
May 8 - Iran announces it will relax some curbs on its nuclear programme, stopping short of violating its 2015 deal with world powers but threatening more action if countries do not shield it from US sanctions