A sprawling undersea search area for a missing Malaysian airliner in the southern Indian Ocean could be extended further south based on new satellite analysis.
It comes just weeks before the multimillion-dollar, year-long sonar hunt for wreckage is due to begin.
Australia's deputy prime minister Warren Truss said analysis of a failed satellite phone call from Malaysia Airlines to Flight 370 "suggests to us that the aircraft might have turned south a little earlier than we had previously expected".
The Boeing 777 disappeared off radar after veering off its northerly course from Kuala Lumpur to Beijing on March 8, and is thought to have crashed 1,800 kilometres (1,100 miles) off Australia's west coast.
The overall search area remains unchanged, Mr Truss said. However, Australian Transport Safety Bureau chief commissioner Martin Dolan said he would meet with international experts next week to decide whether the 60,000 square kilometre (23,000 square mile) targeted search area should be extended or shifted further south based on the new analysis.
"We think we may extend that area farther south; that's the thing we're currently considering," he said.
The new analysis applies to satellite data from the first of two satellite phone calls Malaysia Airlines ground staff attempted to make to Flight 370's crew.
By the time the calls were attempted, the plane had become invisible to civilian radar. It had flown west without communications past Sumatra and beyond the range of Malaysian military radar.
Mr Dolan said the new analysis suggested the jet was already flying south when the first phone call was attempted less than 20 minutes after the plane dropped off military radar.
"Previously, there was the possibility that it could have been quite a bit later, so we had to do our modelling based on a range of possibilities as to where the aircraft turned," he said.
"We're now more confident that it turned comparatively early. That does make a difference to how we prioritise the search along the seventh arc," he added, referring to the area where satellite information from a jet engine transmitter suggests the plane ran out of fuel and crashed.
Investigators have long been aware of the phone call. But they have only recently adapted analysis methodology to glean clues to the plane's direction from the satellite phone data.
The analysis adds weight to an Australian Transport Safety Bureau crash investigation report in June in which most of the modeling of the plane's potential flight paths factored in a relatively early switch to a southerly course.
Investigators are currently attempting to calculate precisely where they should start their search, and an order of priority for other potential crash sites to be examined within the wider area.
The current search area covers an stretch of ocean 700 kilometres (435 miles) long and 80 kilometres (50 miles) wide. An initial search of 850 square kilometres (330 square miles) of seabed to the north ended with officials concluding that they were focusing their efforts in the wrong place.
Mr Truss and Malaysian transport minister Liow Tiong Lai signed an agreement yesterday sharing the ongoing costs between the two countries as the search progresses to the expensive next phase, which could take up to a year and cost 52 million Australian dollars (£29 million).
Until now, each country involved in the search has been bearing its own costs.
In three weeks, Dutch contractor Fugro Survey will begin the operation with three vessels towing underwater vehicles equipped with side-scan sonar, multi-beam echo sounders and video equipment, Mr Truss said.
Mr Liow said investigators had advised that success of the undersea search for wreckage and the aircraft's black boxes with cockpit voice recordings and flight data was crucial to solving the mystery of the disaster.
"The investigation cannot continue without the search result," he said. "We need to find the plane, we need to find the black box in the plane so that we can have a conclusion in the investigation."
Malaysia, as the country where the Boeing 777 was flagged, has overall responsibility for the crash investigation. But Australia has search and rescue responsibility.
Chinese vice-minister of transport He Jianzhong, who also attended the Canberra meeting, said the ministers had all agreed that the search will not be interrupted or given up. Most of the passengers - 153 - were Chinese.