The search for missing Malaysia Airlines Flight MH370 could take up to a year, according to the official leading the search operation.
Speaking in Malaysia, Australian Angus Houston said the authorities remain “totally committed to finding MH370”, but that it could take another eight to 12 months to recover any wreckage.
Mr Houston’s comments came ahead of planned talks between senior officials from Malaysia, Australia and China in Canberra next week, to decide on the next steps in the search for the missing plane.
They expressed confidence that the hunt remains on the right track despite no debris so far being found.
Malaysian Defence Minister Hishammuddin Hussein said the challenges were huge but told reporters: “I believe we will find MH370 sooner or later.”
In pictures: Missing Malaysia Airlines flight MH370
In pictures: Missing Malaysia Airlines flight MH370
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A family member of a passenger aboard the missing Malaysia Airlines flight MH370 burns incense as he prays at Yonghegong Lama Temple in Beijing
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Family members of passengers aboard the missing Malaysia Airlines flight MH370 burn incense to pray at Yonghegong Lama Temple in Beijing
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A family member of a passenger aboard the missing Malaysia Airlines flight MH370 comforts another relative as they gather to pray at Yonghegong Lama Temple in Beijing
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Relatives of passengers on missing Malaysia Airlines flight MH370 cry as they gather at the Lama Temple in Beijing. Chinese relatives marked 100 days since the plane went missing on a flight from Kuala Lumpur, Malaysia to Beijing by offering prayers and burning incense at the buddhist temple
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Relatives of passengers on missing Malaysia Airlines flight MH370 offer prayers at the Lama Temple in Beijing
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A Chinese relative of passengers of Malaysia Airlines flight MH370 prays at the Lama Temple in Beijing
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Chinese relatives of passengers of Malaysia Airlines flight MH370 hold incense sticks and pray at the Lama Temple in Beijing
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Intan Maizura Othman (34) wife of MH370 fligh attendant Hazrin Hasnan holds placard during an event to remember the 100th day of the missing crews and passengers of Malaysian Airlines plane MH370 in Damansara, Selangor
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A young relative tries to stick paper planes on a board during an event to remember the 100th day of the missing crews and passengers of Malaysian Airlines plane MH370 in Damansara, Selangor
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Pictures of crews and passengers is displayed during an event to remember the 100th day of the missing crews and passengers of Malaysian Airlines plane MH370 in Damansara, Selangor
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Chinese police men try to prevent relatives of Chinese passengers onboard the Malaysia Airlines MH370 from marching to the Malaysian embassy from a hotel in Beijing
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Boatswain's Mate, Able Seaman Morgan Macdonald (L) observing markers from a Royal New Zealand Air Force (RNZAF) P3K Orion at sea in the Southern Indian Ocean. An oil slick in the Indian Ocean is not from missing Malaysia Airlines flight MH370, officials said when insisting underwater search efforts would be 'pursued to their completion'
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Craig Turner from Phoenix International monitoring the Artemis' depth and speed as the Autonomous Underwater Vehicle scans the ocean floor for missing Malaysia Airlines flight MH 370 in the southern Indian Ocean
An unmanned submarine continues to scout the Indian Ocean floor off western Australia where sounds consistent with a plane’s black box were detected in early April. Additional equipment is expected to be brought in within the next few weeks to scour an expanded underwater area. The aerial search for surface debris ended this week.
Mr Houston said he was confident the wreckage was in that area but he conceded that the probability of the US Navy's Bluefin 21 robotic sub finding the wreckage is “lower than it was when we started the search”.
He added that the ministerial meeting was crucial to “formalise the way ahead to ensure the search continues with urgency and that it doesn't stop at any stage”.
He also said that Bangladeshi ships, including a vessel fitted with sonar equipment, had so far found nothing in the northern Bay of Bengal, where a resource survey company, Australia-based GeoResonance Pty Ltd, had claimed it found possible plane wreckage.
According to Mr Hishammuddin, Malaysia is still considering whether to hire private deep sea vessels to search the Bay of Bengal area as it could distract the main search and cost involved would be high.
On Thursday fresh questions were raised over air traffic co-ordination after Malaysia released a preliminary report on the final moments of MH370.
According to the five-page report by the Ministry of Transport, Malaysia did not launch an official search and rescue operation until four hours after the jet disappeared on 8 March, instead wasting precious time attempting to track it in the wrong country.
Some 25 minutes after the Malaysian jet was first reported missing over the Gulf of Thailand, the airline told controllers that it had flown onto Cambodian airspace. It later added it had been able to exchange signals, the report said.
Half an hour later, the airline reassured controllers that the Boeing 777 was in a “normal condition” based on a signal placing it even further east, on the other side of Vietnam.
In fact, by then it had flown back west across Malaysia and was already on a new southerly course thought to have taken it across the tip of Indonesia and towards the Indian Ocean, where investigators believe it crashed with 239 people on board.
Unnoticed by civil controllers because its transponder was switched off, and deemed no threat by a military radar controller, the aircraft flew back across Malaysia and the Malacca Straits for an hour while the airline believed it was in Cambodian and then Vietnamese airspace.
The airline later told controllers the information had been based on a “projection” and was not reliable, according to the report.
MH370’s route suggests that it was deliberately flown to avoid detection. David Learmount, an aviation expert, told The Telegraph: “It does look like the plane was trying to avoid Indonesian air space. It was an aircraft that has gone rogue. It didn’t need to follow waypoints. There are no roads in the sky - pilots can go wherever they want.”
On Thursday, Malaysia Airlines urged the families of missing passengers to return to their homes pending further news, and pledged to pay early compensation to those who qualified.
The first funeral services for missing passengers are due to be held in Australia over the weekend.
Additional reporting by agencies