A debris field has been discovered within the search area by a remotely operated underwater vehicle near the Titanic, the US Coast Guard has said.

"Experts within the unified command are evaluating the information," a statement on Twitter added.

A news conference to discuss the findings is scheduled to take place at 8pm UK time tonight.

The debris field was found by a remotely operated vehicle deployed by Horizon Arctic, a Canadian vessel.

The ROV, which is equipped with cameras and sonar, had successfully managed to reach the sea floor.

Sky's US correspondent James Matthews, reporting from Boston, described the updated statement as "significant".

He added: "The word 'debris' doesn't sound good at all in a situation and at a depth where the water pressure is huge."

Titan had disappeared on Sunday in the Atlantic Ocean - 435 miles south of Newfoundland, Canada - during an expedition dive to see the wreck of the Titanic.

Five men are on board: British billionaire Hamish Harding, British businessman Shahzada Dawood, his son Suleman Dawood, OceanGate's US-based chief executive and founder Stockton Rush, and French submersible pilot Paul-Henri Nargeolet.

The US Coast Guard had predicted that the air supply in the vessel would run out at 12.08pm UK time on Thursday.

Ships, planes and underwater craft from multiple countries were deployed to the area with rescuers searching a remote part of the Atlantic Ocean more than twice the size of the US state of Connecticut in waters as deep as 4,020m (13,200ft).