A failed satellite phone call to the crew of the Boeing 777 plane with 239 people, including five Indians and one Indian-origin Canadian, on board on March 8 after it disappeared from radar suggests the jet may have turned south slightly earlier than previously thought during its enigmatic journey, Australia's Deputy Prime minister Warren Truss said.
Australia, which is responsible for search and rescue operations described by officials as the largest in history, has been looking for the plane in southern Indian Ocean, an area about 1,800 km off its west coast.
Truss said details about the failed call is now being used to refine the suspected final path of the plane.
"After MH370 disappeared from the radar, Malaysia Airlines ground staff sought to make contact using a satellite phone. That was unsuccessful," Truss told reporters.
"The search area remains the same but some of the areas, some of the information we now have suggests to us that areas a little further to the south, within the search area but a little further to the south, may be of particular interest and priority in the search area," Truss said.
He said investigators still believed MH370 was somewhere on the search zone's seventh arc, where its flight data communication systems emitted a final satellite "handshake".
Truss said ongoing mapping of 87,000 square kilometres of the ocean floor had uncovered "quite remarkable geographical features" including the discovery of new undersea volcanoes up to 2,000 metres high.
MH370 vanished during a flight that was meant to go from Kuala Lumpur, Malaysia, to Beijing. The search operation has so far turned up no debris from the plane.
Investigators do not know what happened to the flight and finding its "black box" flight recorders is seen as key to understanding the factors behind its disappearance.
Truss and the Malaysian transport minister, Liow Tiong Lai, signed a memorandum of understanding today on co- operation in the search for the missing plane as it progresses to the expensive next phase. The agreement shares the ongoing costs between the two countries.
Australia recently awarded a contract to Dutch engineering firm Fugro to search the sea floor, and the company is already conducting a detailed underwater mapping of the search area, along with a Chinese naval vessel.