The Joint Agency Coordination Centre (JACC) searching for missing flight MH370 says it has completed its search in the Indian Ocean where pings were detected and has discounted the zone as the final resting place of the Malaysia Airlines plane.
In a statement JACC said Bluefin-21 had completed its last mission searching in the vicinity of the acoustic signals detected in April.
It says data from the missions has been analysed, leading the organisation to advise "that no signs of aircraft debris have been found" on the seafloor in the identified area.
Despite ruling out the current search area as the crash site, JACC remains confident they have established the course of the missing plane.
"We know that the aircraft entered the water in a long but narrow arc of the southern Indian Ocean," it said. "The focus of the ATSB's (Australian Transport Safety Bureau) work now is to narrow the search area of this arc."
An 850 square kilometre area of ocean floor has been searched since the Autonomous Underwater Vehicle (AUV) joined the search effort.
The ATSB has advised JACC the search in the area surrounding the acoustic detections is now complete and the zone can "be discounted as the final resting place of MH370".
The US Navy pinger locator, dragged by the Australian ship Ocean Shield, was used by searchers to listen for underwater signals in the remote southern Indian Ocean in an area where satellite data suggested the plane went down.
The data put MH370's last location some 1,600 kilometres off the coast of Western Australia.
In April the pinger locator detected several signals consistent with those emitted by an aircraft black box. The battery in the flight recorder box has since died.
At the time, Prime Minister Tony Abbott expressed confidence that searchers knew where the plane wreckage was, to within a few kilometres.
JACC says it is continuing to examine the signals but is yet to determine what and where they are coming from. It says it is possible the origin of the acoustic detections may never be known.
Federal Transport Minister Warren Truss says the search will continue along the arc but that it will move into a "different phase".
"We are still very confident that the resting place of the aircraft is in the Southern Ocean and along the seventh ping line," he said in a statement to Parliament.
"We concentrated the search in that area because the pings, the information we received was the best information available at the time, and that's all you can do in circumstances like this, follow the very best leads."
Mr Truss says a Chinese ship has begun mapping the ocean floor in the search area ahead of the resumption of the underwater search in August.
"This is a painstaking effort in a very large ocean. The area to be searched under the ... next stage could be as big as 800km in length by 70km wide," he said.
The Minister says there will now be an "extensive" review of all the data associated with the plane's disappearance, which will also be peer reviewed.
Ocean Shield has now departed the search area and is expected to arrive in at the Fleet Base West on Saturday, JACC said.
Eight nations, including Australia, the United States, New Zealand, Malaysia, Japan, South Korea, Britain and China, have been involved in the unprecedented hunt for the aircraft, which went missing en route from Kuala Lumpur to Beijing.
US Navy earlier dismissed officer's search zone claims
The announcement comes hours after the US Navy's deputy director of ocean engineering told CNN there was broad agreement the signals came from some other man-made source unrelated to the plane, which disappeared on March 8 carrying 239 people, including six Australians.
"Our best theory at this point is that [the pings were] likely some sound produced by the ship... or within the electronics of the towed pinger locator," Mr Dean said.
"Your fear any time you put electronic equipment in the water is that if any water gets in and grounds or shorts something out, that you could start producing sound."
The US Navy issued a statement soon after calling Mr Dean's comments "speculative and premature".
"The US has been working cooperatively with our Malaysia, Australian and international partners for more than two months in an effort to locate MH370," a spokesman said.
"Mike Dean's comments today were speculative and premature, as we continue to work with our partners to more thoroughly understand the data acquired by the towed pinger locator.
"As such, we would defer to the Australians, as the lead in the search effort, to make additional information known at the appropriate time."
It comes as Malaysia's government and British satellite firm Inmarsat released data this week to help determine the path of MH370.
Families of the missing passengers are hoping that opening up the data to analysis by a wider range of experts could help verify the plane's last location.
Australian authorities said the data supported the theory that the plane crashed after running out of fuel.
May 29, 2014, 9:13 pm
May they all rest in peace.
And may the families and loved ones accept the fate of those perished.
It will be of no result and endless searching for something that small compare to the width and depth of the ocean.