Searchers scouring the Indian Ocean for Flight MH370 are confident that signals received in the search for MH370 are from the plane's black box, Australian Prime Minister Tony Abbott says.

The West Australian aviation editor, Geoffrey Thomas earlier tweeted: "Black boxes of MH370 may have been found. PM to make announcement at 11.45am [Perth time, 1.45pm AEST]."

However a Prime Minister's staff said this afternoon, "there was no conference planned for 1.45pm".

A spokeswoman for the Joint Agency Coordination Centre, which former Defence chief Angus Houston is heading, would not confirm the reports the black box may have been located.

"There's no further update at this stage," she said. "There's nothing to report."

Mr Houston, the head of the search's Joint Agency Coordination Centre, has previously said authorities believed a number of 'pings' detected by the Australian ship Ocean Shield and and Australia sea patrol aircraft were "from a man-made source".

"The acoustic data will require further analysis overnight but shows potential of being from a man-made source," he said on Thursday night.

The four signals detected since Saturday has seen the search focus honed to about 58,000 square kilometres, from more than 200,000 square kilometres only days ago.