PERTH (AFP) - Australia said on Monday that French satellite data indicating floating objects possibly linked to missing Flight MH370 related to an area outside the current search zone, while admitting to "clutching" at every piece of new information.

Malaysian authorities on Sunday said the data was related to the area of the southern Indian Ocean being scoured for the missing Malaysian jet, which disappeared on March 8 with 239 people on board.

The information was passed to Australia, which is coordinating the hunt for the plane, focused on a remote stretch of ocean 2,500 kilometres south-west of Perth.

But Australian Deputy Prime Minister Warren Truss said the latest potential sighting of debris was about 850 kilometres north of where aircraft and ships have been looking since Thursday.

"Certainly the area where debris has been picked up by satellites is of particular interest, and they're the focus of a lot of the searching," Mr Truss told ABC radio.

"The French sighting is I guess a piece of new material because that is in a completely different location. That is about 850 kilometres north of our current search area.

"So we need to check that out as well."

While Malaysian authorities initially said the latest data came in the form of images, France's foreign ministry clarified this, saying it came in the form of "satellite-generated radar echoes".

A radar echo is an electronic signal that contains information about the location and distance of an object, which bounces the signal back.

Hopes of a breakthrough have been fuelled by satellite images and data captured by Australia, China, and now France in recent days, along with the visual sighting of a wooden pallet and other debris from a spotter plane on Saturday.

But Mr Truss cautioned that "we still don't know for certain that the aircraft is even in this area".

"We're just, I guess, clutching at whatever little piece of information comes along to try and find a place where we might be able to concentrate the efforts," he added.

The Australian Maritime Safety Authority added in a statement on Monday that it "reiterates this is a challenging search operation".

"The flight has been missing since March 8 and AMSA continues to hold the gravest of concerns for the passengers and crew on board the missing flight."

Australian, US and New Zealand planes have been flying sorties for four days looking for the Boeing 777 and AMSA said 10 aircraft were now involved in the search with the arrival of two giant Chinese Ilyushin IL-76 reconnaissance planes along with two Japanese P3 Orions.

"Today's search is split into two areas within the same proximity covering a cumulative 68,500 square kilometres," it said.

"The weather forecast in the search area is expected to deteriorate, with rain likely."

Mr Truss also warned of deteriorating weather, stirred up by Tropical Cyclone Gillian, which is expected to track at least 1,000 kilometres north of the search area.

"Clearly it won't be cyclonic when it gets down into the freezing waters that we're dealing with with this search," Mr Truss said.

"But certainly it could stir up less favourable weather."