MH370 speculation not helpful: Shorten

The search for the missing Malaysia Airlines plane is not being helped by a running commentary about the fate of the flight, Opposition Leader Bill Shorten says.

Authorities say the plane is not in the search zone off the Western Australian coast where acoustic "pings" were detected, but still believe it is in the southern Indian Ocean.

Prime Minister Tony Abbott last month said he was very confident the location of the black box from flight MH370 could be narrowed down to within a few kilometres.

Mr Shorten said the search should continue without speculation about the fate of the flight.

"We've all been touched by the tragedy and the disappearance of MH370," he told reporters in Melbourne on Friday.

"What I think we need to do is have less running commentary and more letting the professionals get on with the job of trying to answer this terrible question."