A Maersk cargo ship was targeted by a missile as it passed the coast of Yemen on Thursday, the Danish company said, amid a series of Yemeni Houthi group attacks on shipping that have prompted the U.S. to push for a naval coalition in the Red Sea.

It was not immediately clear if the Maersk incident was the same as the one maritime security agencies reported in the same area, with a ship being fired on after being ordered to change course and sail to Yemen.

Separately, the maritime security company Ambrey said a Malta-flagged, Bulgarian-owned bulk carrier was reportedly boarded in the Arabian Sea near the Yemeni island of Socotra.

Yemen's Iran-aligned Houthis, who have controlled the capital Sanaa and much of the Red Sea coast since 2014, have attacked ships and fired drones and missiles at Israel since the start of the war in Gaza over two months ago.

The U.S. Special Envoy for Yemen, Tim Lenderking, told Reuters on Thursday that Washington wanted the "broadest possible" maritime coalition to protect ships in the Red Sea and signal to the Houthis that attacks would not be tolerated.

Iran's Defence Minister Mohammad Reza Ashtiani warned that the proposed multi-national naval force would face "extraordinary problems" and nobody "can make a move in a region where we have predominance".

Maersk said its ship Maersk Gibraltar was travelling from Salalah in Oman to Jeddah in Saudi Arabia when it was fired upon near the Bab al-Mandab Strait, linking the Gulf of Aden and Red Sea.

"We call on political action to ensure a swift de-escalation" of the recent attacks in the region, it said, warning that the "current situation puts seafarer lives at risk and is unsustainable for global trade".

Ambrey and the United Kingdom Maritime Trade Operations (UKMTO) said a vessel travelling northwards through the Bab al-Mandab Strait had been ordered to change course and sail to Yemen, and was fired upon when it did not.

Ambrey said the group making the demand had identified itself as the Yemeni navy and was probably the Houthis. UKMTO said a missile blast had struck just 50 meters from the ship's side.

The bulk carrier that Ambrey said was boarded on Thursday had increased and decreased speeds in possible evasive manoeuvres before appearing to be adrift. Ambrey said an Iran-flagged fishing vessel in the vicinity had earlier turned off its transponder.

On Wednesday, maritime sources said a tanker in the Red Sea was fired on by gunmen in a speedboat and targeted it with missiles, while a second commercial vessel was also approached by a speedboat but not attacked.