A US exploration firm said Wednesday it has sent a high-tech vessel in hopes of soon resuming the hunt for flight MH370, whose disappearance is one of aviation's greatest mysteries.

The Malaysia Airlines jet disappeared in March 2014 with 239 people -- mostly from China -- on board en route from Kuala Lumpur to Beijing after diverting from its flight path.

No sign of the plane was found in a 120,000 square kilometre (46,000 square mile) search zone selected by satellite analysis of the jet's likely trajectory.

The sea search -- the largest in aviation history -- was called off in January last year but looks set to resume soon.

Exploration firm Ocean Infinity said it was sending a research vessel to the zone in the southern Indian Ocean and hopes to finalise a deal with the Malaysian government to restart the hunt in the coming days.

"We are moving the vessel, Seabed Constructor, towards the vicinity of the possible search zone," a spokesman for the company told AFP.

"This is designed to save time should the contract award be forthcoming, as hoped."

The Norwegian research vessel being leased by Ocean Infinity set off from South Africa and was aiming to arrive in the search area by mid-January.

The firm wants to start the hunt, which will be on a "no find, no fee" basis, during a period of good weather expected in January and February.

The vessel is carrying several autonomous submarines which can be launched from the ship to scour the seabed for the jet.

Malaysia's Deputy Transport Minister Datuk Aziz Kaprawi confirmed negotiations with Ocean Infinity were in the final stages: "They know we are very serious in taking their offer."

Ocean Infinity was one of three companies which had bid to resume the hunt.

Australia's national science body CSIRO released a report in April suggesting the doomed plane was "most likely" north of the former search zone in an area of approximately 25,000 square kilometres.

Only three confirmed fragments of MH370 have been found, all of them on western Indian Ocean shores, including a two-metre wing part known as a flaperon.

Source: AFP