KUALA LUMPUR (REUTERS) - Malaysia's new government has promised to release a long-awaited report into the disappearance of Malaysia Airlines flight MH370 as a privately funded underwater search effort comes to a close without finding the plane.

Flight MH370, carrying 239 people, vanished enroute from Kuala Lumpur to Beijing on March 8, 2014, becoming one of the world's greatest aviation mysteries.

The government of Prime Minister Mahathir Mohamad said last week that US seabed exploration firm Ocean Infinity, which had scoured the southern Indian Ocean for the aircraft since January, would end its hunt on Tuesday.

In a statement on Tuesday (May 29), Ocean Infinity confirmed that its search "is shortly coming to an end".

Ocean Infinity CEO Oliver Plunkett said their team had searched more than 112,000 square kilometres (43,243 square miles) of ocean floor in a little over three months.

"Part of our motivation for renewing the search was to try to provide some answers to those affected. It is therefore with a heavy heart that we end our current search without having achieved that aim... Whilst clearly the outcome so far is extremely disappointing, as a company, we are truly proud of what we have achieved both in terms of the quality of data we've produced and the speed with which we covered such a vast area," he said, adding that he hoped the company would be able to offer its services again in a future search for the airliner.

The previous administration of Najib Razak, who was defeated in a stunning election upset on May 9, had promised up to US$70 million (S$93.8 million) to the Texas-based firm if it found the plane within 90 days.

Malaysia's transport minister, Anthony Loke, said a full report into MH370's disappearance would be published in the near future, but he did not give a date.

"I can assure you the final report will be published with full disclosure. There will not be any edits, or anything hidden," he told reporters late on Monday.

Asked whether the report would refer to controversial elements of the MH370 case, he said: "To me, whatever elements, we will just publish it".

Last year (2017), Australian authorities said the MH370 captain had flown a route on his home simulator six weeks before the disappearance that was "initially similar" to the course actually taken by the aircraft.

Peter Foley, who led the Australian Transport Safety Bureau's search efforts, told an Australian Senate hearing "control inputs" had been made to fly the airliner off course, but he could not say if one of the pilots had done so.

Malaysian investigators said in 2015 they had found nothing suspicious in the financial, medical or personal histories of the pilots or crew.

FAMILIES CALL FOR REVIEW

The decision to engage Ocean Infinity came after Australia, China and Malaysia ended a fruitless A$200-million (S$202 million) search across a 120,000 square-kilometre expanse of the Indian Ocean last year.

Voice 370, a group representing the relatives of those aboard the flight, has pressed the new government to review all matters related to MH370, including "any possible falsification or elimination of records related to MH370 and its maintenance".

Calvin Shim, whose wife was a crew member on the plane, said he was concerned that the accident report would not include key information such as the plane's full cargo manifest and the results of a separate investigation by Malaysian police.

"We know that this issue is already four years old and a lot of people involved want closure," he said.

"These four years have not been fun to us, the families." Australia's Deputy Prime Minister Michael McCormack said the search had tested the limits of technology and capacity of experts and people at sea.

It would only resume if there was "credible evidence which identifies a specific location of the missing aircraft".

"We will always remain hopeful that one day the aircraft will be located," McCormack's office said in a statement.