While in a press conference in Canberra, Prime Minister Tony Abbott has said the Australia-led search for the missing MH370 is entering a new phase as operatives focused on a larger underwater area.

He added it is now unlikely to find any debris of the plane on the ocean's surface.

"By this stage, 52 days into the search, most material would have become water-logged and sunk. With the distances involved, all of the aircraft are operating at close to the limit of sensible and safe operation.Therefore, we are moving from the current phase to a phase which is focused on searching the ocean floor over a much larger area."

Abbott cited Australia remains committed in solving the mystery surrounding the missing plane.

"While the search will be moving to a new phase in coming weeks, it certainly is not ending," he said.

Air Chief Marshall Angus Houston said the new phase could turn in more positive results but that it could still take months.

"It will take time. I'd invite you all to just have a look at the French experience with their flight 447 - it took them two years to find the final resting place of that aircraft. We are getting into a very challenging task, as the Prime Minister said, probably the most demanding task in search terms that has ever been mounted to look for a lost aircraft."

Hence, the search for MH370 can now cost as much as $60 million as it involve commercial contractors.

"Up [until] now, every nation has been bearing its own costs and, in the case of Australia, we have been essentially using Australian military, assets we would be paying for anyway. No-one should underestimate the degree of responsibility that Australia has here, because this has happened in our search and rescue zone, and there were, after all, six Australia citizens and one Australian resident on that aircraft.We will be seeking some appropriate contributions from other nations involved, but we will ensure that this search goes ahead."