Persian Gulf

Iran rarely reports on mishaps during its exercises, signalling the severity of the incident.
An Iranian official suggested the US shot down one of their own drones by mistake
Three Iranian vessels tried to block the passage of an oil tanker through the Strait of Hormuz, but withdrew after warnings from a British warship, the UK government said. The stand off followed a warning by Donald Trump that US sanctions on Iran would soon be "substantially" increased as part of his drive to curb Iran's nuclear activities and regional behaviour.
Foreign Secretary Jeremy Hunt said he will unveil diplomatic and economic measures on Monday, but what sparked the incident?