Yemen's Houthis on Thursday said they targeted an unidentified British merchant vessel in the Red Sea in the group's campaign to disrupt shipping to protest Israel's operations in Gaza.

Earlier on Thursday, the United Kingdom Maritime Trade Operations (UKMTO) organization said that an explosion was reported at a distance off a vessel's starboard side west of Yemen's Hodeidah.

The vessel and crew were reported safe, UKMTO said. It was unclear whether it was the ship targeted by the Houthis.

The Houthis' attacks on shipping "will persist until the aggression stops and the siege on the Gaza Strip is lifted," the Houthi military spokesperson said in a statement.

The US and Britain have launched strikes on Houthi targets in Yemen and returned the militia to a list of terrorist groups as turmoil from the Israel-Hamas war spreads through the region. US attacked and destroyed Houthi drones on Wednesday as they prepared to launch against vessels in the Red Sea.

The Iran-aligned Houthi militants, who control the most populous parts of Yemen, have launched exploding drones and missiles at commercial vessels since November 19, after Iran's Supreme Leader urged Muslim nations to blockade Israel.

The Gaza conflict has spilled over into other parts of the Middle East. Lebanon's Iran-aligned Hezbollah has traded fire with Israeli troops along the border, and Iraqi-armed groups have attacked U.S. forces in Iraq.