Unidentified material washed up on the Australian coastline is being investigated for possible links to the Malaysia Airlines flight that disappeared last month.

Police have secured the material, which was found 10km east of the town of Augusta at the southern tip of Western Australia state.

However, Australia's transport safety chief has said he was confident the debris was not from flight MH370.

Australian Transport Safety Bureau Chief Commissioner Martin Dolan told ABC Radio that he had looked at detailed photographs of the debris taken by the police.

The material was the first report of suspected debris in weeks.

It is also the first lead since 4 April, when authorities detected what they believed might have been a signal from the Malaysia Airlines plane's black box recorder.

Flight MH370 disappeared on 8 March with 239 people on board.

Dozens of countries are still involved in the search for the wreckage, which is believed to be in the southern Indian Ocean.

However, that search has been hampered by bad weather.

Authorities suspended the air search for the second day in a row today due to heavy rain, low cloud and big seas.

Meanwhile, Malaysia's cabinet has approved the appointment of an international team to investigate the disappearance of the missing flight, the country's acting Transport Minister Hishammuddin Hussein said.

"The main purpose of the international investigation team is to evaluate, investigate and determine the actual cause of the accident so similar accidents could be avoided in the future," Mr Hussein told reporters in Kuala Lumpur.

He said the government has had talks with Malaysian state oil firm Petronas and other unidentified entities to expand the deep-sea search for the missing plane in the southern Indian Ocean.

A Bluefin-21 drone is nearing the end of its first assignment scouring a 10sq.km stretch of seabed where authorities traced what they believed was a black box signal two weeks ago.

Search officials have said that once the Bluefin-21's current mission, about 1,200 miles northwest of Perth, is finished, they will redeploy the submarine to other areas yet to be determined.

Australia vows to keep searching

Australia has promised to keep searching for the missing plane.

Australian Prime Minister Tony Abbott admitted the search strategy may change if seabed scans taken by a US Navy drone failed to turn up a trace of the plane.

"We may well re-think the search but we will not rest until we have done everything we can to solve this mystery," he said.

"The only way we can get to the bottom of this is to keep searching the probable impact zone until we find something or until we have searched it as thoroughly as human ingenuity allows at this time."

The Bluefin-21 drone, a key component in the search after the detection of audio signals or "pings" believed to be from the plane's black box flight recorder, is due to end its first full mission soon.

The Australian and Malaysian governments are under growing pressure to show what lengths they are prepared to go to in order to give closure to the grieving families of those on-board the flight.

In a sign of the families' growing desperation for answers, a group purporting to be relatives of the missing published a letter to Mr Hussein.

They urged the government to investigate old media reports that the plane landed in Kandahar in Afghanistan.

"It is high time that the government should start thinking out of the box by exploring and re-examining all leads, new and old," said the letter, published on Facebook today.