It comes just one day after a general in Tehran threatened to seize a UK ship in retaliation after Royal Marines captured an Iranian supertanker.

On Saturday, maritime tracking programs showed British-flagged crude oil tanker Pacific Voyager had come to a halt, and listed its status as “not under command”, stoking fears that Iran had retaliated.

Whitehall sources, however, told The Telegraph that the situation was a “routine matter.”

“There’s nothing going on. The ship is just drifting because it’s early for its next port. It hasn’t issued any distress signals or shown any problems on board,” the sources said.

The United Kingdom Maritime Trade Operations (UKMTO), which coordinates shipping in the Persian Gulf, said later that the ship was “safe and well”. The UKMTO, had been in direct contact with the vessel, an official said.

Iran dismissed as “fabricated” reports that the ship had been seized by its Revolutionary Guard forces. Iranian sources quoted unnamed senior Iranian government sources denying the boat had been seized.

An oil tanker carrying Iranian oil was illegally seized by British Royal Marines in Gibraltar on Thursday. British Ambassador to Tehran Robert Macaire was summoned to the Ministry of Foreign Affairs later in the day. Iran has described the UK move as ‘unacceptable’ and ‘tantamount to maritime banditry’, highlighting that Britain has no right to impose its own unilateral sanctions or those of the European Union in an extraterritorial manner against the other countries.

British forces seized the supertanker accusing it of carrying crude oil to Syria in violation of European Union (EU) sanctions against the Arab country.

“If Britain does not release the Iranian oil tanker, it is the authorities’ duty to seize a British oil tanker,” said Mohsen Rezai, head of the country’s influential Expediency Council.

“Islamic Iran in its 40-year history has never initiated hostilities in any battles, but has also never hesitated in responding to bullies,” he added.

The Pacific Voyager, passed through the strait of Hormuz en route to the Saudi port of Ras Tanura on Friday. It is Japanese-owned, operated by a Singaporean company, and hired by a subsidiary of a South Korean firm.