A drone hit a vessel in the Gulf of Aden off Yemen, a British maritime security agency said Wednesday, shortly after Yemen's Houthi rebels vowed more attacks on Israeli-linked ships to press Israel to halt its hostilities in Gaza and allow aid into the besieged strip.

A "vessel has been hit on the port side by an Uncrewed Aerial System", the United Kingdom Maritime Trade Operations (UKMTO) agency said, adding that a fire on board had been extinguished and the "vessel and crew are safe".

In a post on X, formerly Twitter, the agency said Wednesday's incident happened 60 nautical miles southeast of the port of Aden, and added: "Vessels are advised to transit with caution and report any suspicious activity to UKMTO."

British maritime risk management company Ambrey said the vessel was a Marshall Islands-flagged bulk carrier.

It said it had been heading "east along the Gulf of Aden when it was struck by a UAV on the port side and on the gangway" which was damaged.

Ambrey said an Indian warship was in contact with the bulk carrier.

There was no immediate claim of responsibility for the attack.

Earlier Wednesday, Houthi spokesman Mohammed Abdelsalam told Al Jazeera TV the rebels would keep up their attacks on Red Sea shipping following a US decision to put the group back on a list of "terrorist" entities.

"We will not give up targeting Israeli ships or ships heading towards ports in occupied Palestine... in support of the Palestinian people," he told the Qatar-based broadcaster.

He said the Houthis would respond to new strikes on Yemen by the United States or Britain, despite already facing multiple rounds of air strikes in response to their targeting of Israeli-linked vessels.