The search by a private US company for Malaysia Airlines Flight 370 will end next week, Malaysia's transport minister has said, while families of those who died onboard urged the government to review all matters related to the jet's disappearance four years ago.

Malaysia signed a "no cure, no fee" deal with Texas-based Ocean Infinity in January to resume the hunt for the plane, a year after the official search in the southern Indian Ocean by Australia, Malaysia and China was called off.

So far, the search has not turned up anything that could shed light on one of the world's biggest aviation mystery.

Transport Minister Anthony Loke said that the 90-day search deal with Ocean Infinity was due to end in April but was extended twice until May 29 following the firm's request.

"There will be no more extensions. It cannot continue forever. Let's wait until May 29 and we will then decide how to proceed," he told AP.