The 13-day search for Malaysia Airlines flight 370 could be close to resolution after satellite images picked up what appears to be a 24-metre long bobbing object in waters off the Australian coast.

But the Australian Maritime Safety Authority said efforts by aircraft to locate the objects were being hampered by poor visibility and weather on scene.

The possible breakthrough, revealed by Prime Minister Tony Abbott in Parliament on Thursday afternoon, could bring resolution for the families of the 239 missing passengers following a massive international land and sea search involving dozens of countries.

The maritime authority said on Thursday it had not been able to confirm if the objects located by satellite 2500 kilometres south-west of Perth were debris from the missing plane.

The authority said the objects spotted were "indistinct" but the sightings had been assessed and were credible.

John Young from AMSA's emergency response division said the objects were of a reasonable size and "probably awash with water bobbing up and down under the surface".

He said the largest object had been assessed as measuring 24 metres, with "another one that's smaller than that" and a number of other images located in the vicinity of the largest object.

"We have to get there, find them, see them, assess them," he said, to confirm if the images were debris from the missing plane.

"The weather is not playing the game with us. We may get a sighting, we may not."

He said water in the search area would be several thousand metres deep.

"This is a lead, it's probably the best lead we have right now, but we need to get there, find them, see them, assess them to know whether it's really meaningful or not and I caution again they will be difficult to find."

Four aircraft have been deployed to locate the floating objects in the area.