By Angela Dewan, CNN

(CNN) -- The search for flight MH370 will end next week after more than four years, at a cost of tens of millions of dollars spent and with no clue of what happened to the ill-fated plane.

Malaysia's cabinet agreed to a request by the US company operating the search, Ocean Infinity, to extend the hunt until May 29. Malaysian Minister of Transport Anthony Loke Siew Fook told reporters in Kuala Lumpur on Wednesday there would be no more extensions after that.

The Malaysian Airlines flight disappeared in 2014 carrying 239 people from Kuala Lumpur to Beijing, in what has become one of the world's biggest aviation mysteries.

The initial search, carried out by Malaysia, China, and Australia, was called off in January last year after failing to find any trace of the plane within a 710,000-plus square kilometer area of the Indian Ocean.

The search is estimated to have cost some 200 million Australian dollars ($151 million), according to Australia's minister for infrastructure and transport, Darren Chester. Most of the funds were provided by the Malaysian government. It has been the most expensive search for a missing plane in history.

Ocean Infinity took over after the initial joint search failed on a no-find, no-fee basis.

The only physical sign of the plane has been debris that washed up in eastern Africa and nearby islands, far from where experts believed the flight disappeared. A wing fragment and part of the plane's flaperon are among the remnants that have turned up.

Several theories on what might have happened to the flight have been put forward, including pilot suicide.

Australian investigators who led the joint search for the flight over four years dismissed that theory and have defended their belief that the plane's disappearance was due to an accident.

Peter Foley and Greg Hood from the Australian Transport Safety Bureau told a parliamentary hearing Tuesday that the plane had likely crashed into the Indian Ocean after running out of fuel.