Iran said on Friday that it had seized a British oil tanker in the Persian Gulf, and the tanker’s owner said it had lost contact with the vessel as it appeared to be heading towards Iran. The British government said it was urgently seeking information about the incident.

The possible seizure of the ship, the Stena Impero, in the Strait of Hormuz, was the latest in three months of escalating tensions between Iran and the West. It came a day after the US claimed it had downed an Iranian drone in the area, which the Iranians denied.

Britain and Iran have been embroiled in a dispute for the past few weeks over Britain’s seizure of an Iranian tanker near Gibraltar. Iran had vowed to retaliate.

Iran’s Fars News Agency said the Stena Impero had been impounded because it was “violating maritime rules and regulations”.

The ship’s owners issued a statement that the Stena Impero had been “approached by unidentified small crafts and a helicopter during transit of the Strait of Hormuz while the vessel was in international waters”.

“We are presently unable to contact the vessel which is now heading north toward Iran,” the owners, Stena Bulk, and the ship’s managers, Northern Marine, said in the statement.

The British defence ministry said it was urgently looking into what happened to the Stena Impero, a 30,000-ton British-flagged ship, which was heading for Saudi Arabia when it abruptly left the international sea lanes through the Strait of Hormuz.

Earlier Friday, Iranian officials denied that the American military had downed an Iranian drone in the Strait of Hormuz, a day after President Trump and Pentagon officials first made that claim.

A spokesman for the Iranian Armed Forces, in rejecting Trump’s assertion, also said that the “unfounded claim” had been intended to increase tensions in the Persian Gulf, according to Tasnim.

Further protection must be provided for merchant vessels after a British flagged tanker was seized by the Iranian Revolutionary Guards in the Strait of Hormuz, the head of the UK Chamber of Shipping said on Friday.

“We condemn unreservedly the capture of Stena Impero as she transited the Strait of Hormuz earlier today,” the chamber’s chief executive, Bob Sanguinetti, said.

“This incident represents an escalation. Whilst we call for measured response, it is also clear that further protection for merchant vessels must be forthcoming.”