Authorities are closing in on the flight recorder from missing Malaysia Airlines plane MH370, Tony Abbott says.

Prime Minister Tony Abbott has briefed Chinese President Xi Jinping about the search for missing aircraft MH370, warning him there could be a long and painstaking road ahead.

Mr Abbott on Friday updated President Xi on the Australian-led search effort for the Malaysia Airlines plane in the Indian Ocean during a bilateral meeting at the Great Hall of the People in Beijing.

The prime minister said Australian authorities had very much narrowed down the search area to some kilometres after receiving “strong detections” from what they’re confident is the plane’s black box.

But he didn’t mince words, warning his Chinese counterpart there was still a long way to go.

“This will be a very long, slow and painstaking process,” he said.

Mr Abbott’s comments came after a day of somewhat mixed messages from authorities leading the search for MH370, which has been missing for five weeks, since March 8.

The prime minister told business leaders in Shanghai on Friday that the search in the Indian Ocean was narrowing.

“We are confident that we know the position of the black box flight recorder to within some kilometres,” Mr Abbott said.

However, those comments appeared to be contradicted a short time later by Australian search coordinator, retired Air Chief Marshal Angus Houston, who indicated there was little change in the search area.

“On the information I have available to me, there has been no major breakthrough in the search for MH370,” Mr Houston said.

He said signals apparently detected by an Australian search aircraft on Thursday were ruled not to have come from a black box flight recorder.

The Joint Agency Coordination Centre issued a statement on Friday morning saying the search area still totalled 46,713 square kilometres – vastly different from Mr Abbott’s statement.

Nonetheless, there remains strong hope that the flight’s all-important black box recorder could be found.

Its batteries are expected to expire soon, so time remains critical.

The Australian vessel Ocean Shield has to date recorded four signals that are believed to have come from at least a black box recorder.

The Ocean Shield on Friday was in an area about 2200km northwest of Perth continuing sweeps of its pinger locator to detect further signals.

Orion aircraft were also continuing acoustic searches.