Australian Prime Minister Tony Abbott expressed optimism over the hunt for missing flight MH370 during an official visit to China yesterday - despite the search chief's insistence there had been no new breakthrough.
Abbott said after attending a luncheon in Shanghai: "We have very much narrowed down the search area and we are very confident that the signals we are detecting are from the black box on MH370."
He said the hunt was focused on a narrow zone in the southern Indian Ocean and officials "knew the position of the black box flight recorder to within some kilometres", Xinhua reported.
Abbott, who later met President Xi Jinping in Beijing, warned that recovering the flight data and cockpit voice recorders would still be a "long, slow and painstaking process".
Abbott's optimism was in contrast to comments from the head of the agency co-ordinating the search effort, retired air chief marshal Angus Houston.
He said the fifth and latest "ping" signal, detected on Thursday, was not related to MH370.
And Houston cautioned that the Joint Agency Co-ordination Centre would not be rushed into deploying underwater vessels to search for the recorders.
He said yesterday in a statement that appeared to contradict Abbott's assertions: "A decision as to when to deploy the autonomous underwater vehicle will be made on advice from experts … and could be some days away.
"There has been no major breakthrough in the search."
The recorders may help investigators solve the biggest mystery in modern aviation history.
The Malaysia Airlines plane was carrying 239 people - 154 of them Chinese - when it vanished on March 8 on its way from Beijing to Kuala Lumpur.
The flight changed course and headed in the opposite direction.
The hunt has brought together more than 25 countries, but only a few of them are equipped with the deep-water technology needed to retrieve the recorders. Pings detected in the search are believed to have come from a depth of 4,500 metres.
The black boxes from Air France flight 447, which crashed into the mid-Atlantic in 2009, were retrieved at 4,000 metres.
Stefan Williams, a professor of marine robotics at Sydney University, said the Australia-led search team lacked the necessary equipment.
But he added: "There are remotely controlled vehicles available which are capable of operating at those depths. Deep water equipment is designed to go down to 6,000 metres. The US in particular has a number of systems used previously in the search for the Air France flight."
After Malaysia announced the delay of a diplomatic trip to China next week, Beijing postponed the delivery of two goodwill pandas scheduled to arrive in Kuala Lumpur on Wednesday until an "appropriate time".
Additional reporting by Associated Press