The sample of an oil slick detected on Sunday by the Australian defence vessel Ocean Shield in the southern Indian Ocean, where a search is going on for a missing Malaysian airliner, has been brought here for analysis.

The Joint Agency Coordination Centre (JACC), which is overseeing the search operation for Malaysia Airlines Flight MH370 that entered its 41st day Thursday, said the results of the analysis would be announced once they were available.

On Monday, JACC chief coordinator Air Chief Marshal (Rtd) Angus Houston told a press conference that the oil slick was detected about 5,500m within the vicinity of 'pings' previously detected by the towed pinger locator used by the Ocean Shield.

Two litres of the oil slick were collected as the sample.

In a statement, JACC said the autonomous underwater vehicle (AUV) called Bluefin-21 had, until Thursday morning, searched about 90 sq km and data from its latest mission was being analysed.

"Overnight, Bluefin-21 AUV completed a full mission in the search area and is currently planning for its next mission," the statement said.

Data collected from its two previous missions had found nothing so far.

Bluefin-21, a probe equipped with side-scan sonar that uses acoustic sounds to create a 3D map of the sea floor, has been deployed in the hope of locating any debris of the missing plane.

It was dispatched on its maiden mission from the Ocean Shield to a 40 sq km area to continue the search for MH370 underwater, as no further confirmed signals were picked up by the towed pinger locator since April 8.

The statement said up to 10 military aircraft, two civil aircraft and 11 ships would be involved in Thursday's search operation.

JACC said the Australian Maritime Safety Authority had planned a visual search area totalling about 40,349 sq km, lying about 2,170 km northwest of Perth.

"The weather forecast for today is isolated showers and southeasterly winds," it added.

Flight MH370, with 239 people aboard, left the KL International Airport at 12.41 am on March 8 and disappeared from radar screens about an hour later while over the South China Sea. It was to have arrived in Beijing at 6.30 am on the same day.

A multinational search was mounted for the Boeing 777-200 aircraft, first in the South China Sea and then, after it was learnt that the plane had veered off course, in the southern Indian Ocean.

After an analysis of satellite data indicated that the plane's last position was in the middle of the Indian Ocean, west of Perth, Australia, Malaysian Prime Minister Datuk Seri Najib Tun Razak announced on March 24 that Flight MH370 "ended in the southern Indian Ocean".