A UK-flagged supertanker that came to a halt in the Gulf early on Saturday is "safe and well", a United Kingdom Maritime Trade Operations (UKMTO) official told Reuters.

The Pacific Voyager oil tanker stopped as part of a routine procedure to adjust its arrival time at its next port of call and has since continued on its way, the official said.

The UKMTO, which coordinates shipping in the Gulf, had been in direct contact with the vessel, the official said.

Iran had dismissed as "fabricated" reports that the ship had been seized by its Revolutionary Guard forces.