Australia said it will not abandon the search for the missing Malaysia Airlines plane, insisting that the cost of the operation is not a concern.
PM Tony Abbott said if the current underwater search was unsuccessful, a new strategy would begin, BBC reported.
Defense Minister David Johnston has said that powerful sonar equipment will probably be used in the next stage.
The plane was carrying 239 people from Kuala Lumpur to Beijing when it disappeared in March.
A US Navy Bluefin-21 mini-submarine scanning the ocean bed has covered more than 80% of a 310 sq. km (120 sq. mile) search area in the Southern Indian Ocean, without finding any sign of debris in water that is up to 4.5km deep.
Abbott said the probable impact zone of the airliner was in an area of the sea floor 700km (430 miles) long and 80km (50 miles) wide.
Source: FARS
