Malaysia is pulling out a vessel contracted by the country to search for the missing Malaysia Airlines Flight MH370. The search effort, which is jointly funded by Malaysia and Australia, has continued for over a year, and has become the most expensive search operation in commercial aviation history.

Daniel O’Malley, a spokesman for the Australian Transport Safety Bureau (ATSB), which is leading the search for the Boeing 777-200 told International Business Times over the phone on Thursday that the Malaysian government will terminate the GO Phoenix's operations in the search zone in the southern Indian Ocean Friday. The vessel had deployed a remote-operated side-scan sonar vehicle that can operate at depths of nearly 20,000 feet.

“The vessel GO Phoenix, and the experts and equipment aboard are contracted by Malaysia. The Malaysian Government has advised that the contract will end with the completion of the current swing,” O’Malley said, in an emailed statement.

About 19,000 square miles of a planned 46,000-square-mile search zone -- located about 1,100 miles off the western coast of Australia -- has been scoured so far for signs of the missing plane. Flight MH370 was carrying 239 people when it went missing on its way to Beijing from Kuala Lumpur. 

The GO Phoenix, which is operated by Maryland-based Phoenix International, had returned to the search area on Tuesday, after completing “repairs on the damaged support frame for the deep tow system,” the Joint Agency Coordination Centre (JACC) said, in a search update on Wednesday. 

“Winter conditions are expected to continue to hamper the search,” O’Malley told The Daily Beast. “This means several days of poor weather at a time as fronts pass through the area with several days of more benign conditions in between the fronts. We have excellent weather forecasting systems for the search area, and will take advantage of the periods of better weather to continue the search.”

Two other search vessels -- Fugro Discovery and Fugro Equator -- operated by Dutch company, Fugro NV, recommenced search operations on Tuesday.

Earlier this month, industry experts criticized Australia’s decision of choosing Fugro NV for the search operation, claiming that the company’s search methods were ineffective, and that it was using the wrong technology and inexperienced personnel. However, ATSB refuted the assertions and defended its handling of the search for Flight MH370.

“These attacks are unfounded and unfair,” Martin Dolan, the chief commissioner of ATSB said, in a statement. “The search for MH370 represents thousands of hours of work by hundreds of people who are dedicated, expert and professional. They are fully committed to finding the aircraft.”