The "extraordinarily difficult" search for the missing Malaysia Airlines plane will go on for as long as possible, Australian Prime Minister Tony Abbott has said.
He said the best brains in the world were trying to solve the mystery of what happened to flight MH370, which vanished more than three weeks ago with 239 people on board.
Ten aircraft and 10 ships are now searching the ocean 1,200 miles (2,000km) off the western coast of Australia for debris from the Boeing 777, which was travelling from Kuala Lumpur in Malaysia to the Chinese capital Beijing.
Speaking at Pearce Airbase in Perth, which is home for the search teams scouring the southern Indian Ocean, Mr Abbott said crews were "well, well short" of any point where they would scale back their efforts.
Mr Abbott pledged: "If this mystery is solvable, we will solve it."
People light candles during a vigil to remember passengers of flight MH370 He told journalists at a news conference: "I'm certainly not putting a time limit on it. We can keep searching for quite some time to come and we will keep searching for quite some time to come."
"The intensity of our search and the magnitude of operations is increasing, not decreasing."
Mr Abbott rejected suggestions his Malaysian counterpart had been too quick to say the plane had crashed into the ocean.
"No, the accumulation of evidence is that the aircraft has been lost and it has been lost somewhere in the south of the Indian Ocean," he said.
Najib Razak said last week that based on satellite evidence the plane had crashed in the southern Indian Ocean. Malaysian authorities believe the flight was deliberately diverted off course.
Prime Minister Tony Abbott on his visit to the base The majority of the passengers on board were Chinese, and Beijing has been critical of Malaysia's handling of the investigation.
But the official China Daily newspaper said in an editorial today that it was understandable that not all sensitive information could be made public.
It comes as Chinese relatives of passengers fly to Malaysia to demand an apology, accusing officials there of "delays and deception".
"Although the Malaysian government's handling of the crisis has been quite clumsy, we need to understand that this is perhaps the most bizarre incident in Asian civil aviation history," the editorial said.
Monday's search involves 10 aircraft and 10 ships "Public opinion should not blame the Malaysian authorities for deliberately covering up information in the absence of hard evidence."
The search area is close to an area of the Indian Ocean where the currents drag rubbish and flotsam.
A number of objects have been spotted, but none of those retrieved so far has been from the plane.
One of the vessels due to join the search in the coming days is an Australian defence force ship that has been fitted with a US black box locator and underwater drone.
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