The UK Maritime Trade Operations has warned of an unspecified incident and is urging “extreme caution”.
The maritime safety group, which is part of the Royal Navy, put out the alert early this morning and said it was investigating.
Iranian media claimed claimed there had been explosions on two oil tankers.
The Gulf of Oman connects the Arabian Sea with the Strait of Hormuz, which then runs to the Persian Gulf.
It borders Iran and Pakistan on the north, Oman on the south, and the United Arab Emirates on the west.
This is a breaking story. More to follow.