The latest possible lead came as the search for Malaysian Airlines Flight MH370 entered its third week, with still no confirmed trace of the Boeing 777.

An international force resumed its search efforts on Sunday, zeroing in on two areas about 2500 kilometres south-west of Perth in an effort to find the object identified by China and other small debris including a wooden pallet spotted by a search plane on Saturday.

"New Chinese satellite imagery does seem to suggest at least one large object down there, consistent with the object that earlier satellite imagery discovered," Mr Abbott told reporters in Papua New Guinea, where he is on a visit.

"It's still too early to be definite, but obviously we have now had a number of very credible leads and there is increasing hope - no more than hope - that we might be on the road to discovering what did happen to this ill-fated aircraft," he told reporters.

The new Chinese discovery was dramatically announced by Malaysia's acting Transport Minister, Hishammuddin Hussein, on Saturday after he was handed a note with details during a news conference in Kuala Lumpur.

China said the object was 22 metres long and 13 metres wide, and was spotted about 120 kilometres "south by west" of potential debris reported by Australia off its west coast in the forbidding waters of the southern Indian Ocean.

The new image was captured early on March 18, China's State Administration of Science, Technology and Industry for National Defence (SASTIND) said on its website.

It could not easily be determined from the blurred images whether the objects were the same as those detected by Australia, but the Chinese photograph could depict a cluster of smaller objects, a senior military officer from one of the 26 nations involved in the search for the plane said.

The wing of a Boeing 777-200ER is approximately 27 metres long and 14 metres wide at its base, according to estimates derived from publicly available scale drawings. Its fuselage is 63.7 metres long by 6.2 metres wide.

Flight MH370 vanished from civilian radar screens early on March 8, less than an hour after taking off from Kuala Lumpur on a scheduled flight to Beijing.

Investigators believe someone on board shut off the plane's communications systems, and partial military radar tracking showed it turning west and recrossing the Malay Peninsula, apparently under the control of a skilled pilot.

That has led them to focus on hijacking or sabotage, but they have not ruled out technical problems.

Faint electronic "pings" detected by a commercial satellite suggested it flew for another six hours or so, but could do no better than place its final signal on one of two vast arcs.

While the southern arc is now the main focus of the search, Malaysia says the search will continue in both corridors until confirmed debris is found.

The Australian Maritime Safety Authority (AMSA) said eight aircraft would be scouring two areas covering 59,000 square kilometres on Sunday, following news of the Chinese discovery.

"AMSA plotted the position and it fell within yesterday's search area. The object was not sighted during yesterday's search," it said in a statement.

[New lead: The note handed to Malaysia's acting Transport Minister Hishammuddin Hussein regarding the new satellite images.]

New lead: The note handed to Malaysia's acting Transport Minister Hishammuddin Hussein regarding the new satellite images. Photo: Reuters

"AMSA has used this information in the development of the search area, taking drift modelling into account."

An Australian naval vessel is now in the area, with a small flotilla of Chinese ships heading to the search zone in the coming days. Merchant ships that had been involved in the search had been released, AMSA said.

Japan and India were also sending more planes and Australian and Chinese search and navy vessels are steaming towards the southern search zone.

The first Chinese aircraft heading to Perth to join the hunt landed at the wrong airport on Saturday, underscoring the difficulties facing the increasingly complex multinational search effort.

The Chinese aircraft will be ready to take part in searches on Monday, AMSA said.

NASA to help

NASA will check satellite data and point space-based imaging equipment at the search area to assist with the search for the missingplane, CNN reports.

The Earth-Observing-1 (EO-1) satellite and the ISERV camera on the International Space Station would be able to provide images with a resolution that could be used to identify objects of about 30 metres or larger.

Reuters, smh.com.au

A Chinese satellite has identified another object in the Indian Ocean that could be from the missing Malaysia Airlines flight MH370.

The object is about 22.5 metres long and 13 metres wide.

The high-definition earth observation satellite Gaofen-1 spotted the object at around midnight on March 18, according to China’s State Administration of Science Technology and Industry for National Defence (SASTIND).

Chinese ships and planes were heading towards the area on Saturday night.

The New York Times reported the debris was spotted about 120 kilometre from where two objects were seen two days earlier by a commercial satellite.

New lead: The note handed to Malaysia's acting Transport Minister regarding the new satellite images. The dimension of debris were incorrect in the note and are now reportedly 22.5 metres long and 13 metres wide. Photo: Reuters

The object is in the area of one of two possible routes that investigators say they think Flight 370 took, The Times reported.Defense Minister Hishammuddin Hussein of Malaysia told reporters that the Chinese “will be sending ships to verify.”

Dr John Blaxland, a senior fellow from Australian National University (ANU) said in a telephone interview with media agency, Xinhua, on Saturday that if the measurements of the object were correct, they were consistent with a wing of a Boeing 777 airliner.

Asked about whether the newly spotted object would be the one sighted in an earlier satellite image, Dr Blaxland, from ANU's Strategic and Defense Studies Centre, said they don't seem to be the same object.

"It's similar shaped, but if the measurements (are correct), then this is slightly wider," he said.

The Australian Maritime Safety Authority (AMSA) appeared to downplay the latest finding, stating it had searched the area earlier on Saturday and sighted no such debris.

But it said further attempts would be made when the search resumed on Sunday to establish whether the objects spotted are related to the missing MH370.

It said China provided the satellite image to Australia on Saturday night.

"AMSA has plotted the position and it falls within Saturday’s search area. The object was not sighted on Saturday," the statement continued.

Despite that, the search team would take the information into account when plotting today's search plans.

China's embassy in Kuala Lumpur advised Malaysian authorities of the sighting late on Saturday.

Malaysia's acting Transport Minister Hishammuddin Hussein announced the finding after being handed a note during a press briefing where he expressed concern about a category one cyclone forming in the Indian Ocean near Christmas Island.

Ships from China and other nations joining the search may have to pass through the cyclone danger area, Mr Hishammuddin said.

Mr Hishammuddin said conditions in what has been identified as a ''southern corridor'' search area of the Indian Ocean have been extremely challenging with ocean depths as much as 7000 metres.

Malaysian authorities said the transcript of a purported recording of the conversations between the pilots and air traffic control in Kuala Lumpur before MH370 inexplicably turned around over the South China Sea on Match 8 was inaccurate.

But Azharuddin Abdul Rahman, director-general of Malaysia's civil aviation department, declined to say how the transcript was inaccurate.

Mr Hishammuddin told journalists investigators are still analysing the conversations and the transcript would not be made public. But he said there did not appear to be anything ''abnormal'' in the conversations.

- SOPHIA PHAN

An Australian civil aircraft reported sighting a number of small objects during the search for Malaysia Airlines flight MH370, the Australian Maritime Safety Authority said in a statement at midnight on Sunday.

Prime Minister Tony Abbott says it was too early to be sure if they are from the missing Malaysia Airlines plane.

Mr Abbott gave an update on the search for Flight MH370 before leaving Papua New Guinea on Sunday morning.

They were seen with a naked eye, among them a wooden pallet, within a radius of five kilometres in the southern Indian Ocean, the agency said.

A Royal New Zealand Air Force P3 Orion aircraft was diverted to the location, but reported sighting only clumps of seaweed.

The aircraft dropped a marker buoy to track the movement of the material and a merchant ship has been tasked to locate and identify it.

AMSA said the object was not found during Saturday’s search.

The Royal Australian Air Force, the Royal New Zealand Air Force and two chartered civil aircraft supported Saturday’s search for wreckage.

Since ASMA assumed co-ordination of the search on Monday more than 150 hours of air time has been committed by the air crews to the task.

The Royal Australian Navy’s HMAS Success and two merchant ships are also in the search area.

Further attempts will be made today to establish whether the objects sighted are in fact related to the missing flight MH370.

Mr Abbott said four more aircraft - two Chinese and two Japanese planes - would join the Indian Ocean search on Sunday.

ASMA said this information, which was provided to Australia on Saturday, would be taken into account during Sunday's search.

Hours earlier China released a grainy March 18 satellite image of an object measuring 22.5 metres by 13 metres, just 120 kilometres from where possible wreckage was detected in the ocean two days earlier, about 2500 kilometres south-west of Perth.

The new Chinese satellite imagery suggests at least one large object, Mr Abbott said on Sunday.

"Yesterday one of our civilian search aircraft got visuals of a number of objects in a fairly small area in the overall Australian search zone," he told reporters.

A wooden pallet was among the items, he said.

"Obviously before we can be too specific about what it might be, we need to recover this material. It's still too early to be definite," he said.

Mr Abbott says there is increasing hope that authorities are on the road to discovering what happened to the ill-fated jet.

The floating object captured in the Chinese satellite image falls into Australia’s search area.

MH370, carrying 239 people including six Australians abd two New Zealanders, dropped off civilian radar on March 8 en route from Kuala Lumpur to Beijing. Two weeks later Malaysian investigators still believe it was "deliberately diverted" by someone on board.

- smh.com.au, with AAP, Melanie Kembrey