The hunt for Malaysia Airlines Flight 370 will resume after the government agreed to pay a U.S. exploration company as much as US$70 million if it solves modern aviation's biggest mystery.

The Boeing Co. 777 aircraft disappeared on March 8, 2014, on its way to Beijing from Kuala Lumpur with 239 people on board. The government signed a contract with Ocean Infinity on Wednesday, but said the company would only be paid if it locates the aircraft or flight recorders.

"It is my hope that we will find the answer that we seek for nearly four years and bring some closure to this unfortunate incident," Malaysian Transport Minister Liow Tiong Lai said at a press conference outside Kuala Lumpur.

After combined efforts by the governments of Australia, China and Malaysia failed to locate the vanished aircraft, the new search will be carried out in a remote stretch of the Indian Ocean west of Australia. Authorities have identified the 25,000 square kilometer area as the wreck's most likely resting place before they abandoned their attempts last year.

The vessel Seabed Constructor is on her way to the area with 65 crew on board, with the search due to begin in mid-January, Liow said. The government is pledging US$20 million if the aircraft or both flight recorders are found within 5,000 square kilometers of the primary search area, with the reward topping off at US$70 million if it's found in a search area exceeding 25,000 square kilometers.

Investigators believe MH370 headed south over the Indian Ocean for about six hours before plummeting into the water. While no bodies have ever been recovered, a few fragments of the jet have turned up on Africa's eastern seaboard. The previous search effort and the wreckage found have allowed researchers to revise their assessments on the search area, underpinning Ocean Infinity's confidence in finding the aircraft, CEO Oliver Plunkett said.