Underwater search for MH370 to resume in 'probable impact zone'

A Royal Australian Air Force Orion from 92 Wing dropping stores to HMAS Toowoomba during the search for MH370 in April.

An underwater search for Malaysia Airlines flight MH370 will resume off Western Australia in about a month, Tony Abbott says.

The Australian Prime Minister says he's a long way from giving up on the fight for answers, and he feels deeply for the Australian families who lost loved ones.

"(They have) no closure, it's terrible," Mr Abbott told ABC radio in Brisbane on Wednesday. He said there was a reasonable chance that the private contractor commissioned to hunt for the plane would find it, if it was within the search arc.

"They are now going to search the entire probable impact zone which is, from memory, something like 60,000 square kilometres of the ocean floor, off the coast of Western Australia," he said.

"My understanding is that they are going to start in the next month or so, but the search could take up to a year."

Mr Abbott said the government was determined to do the right thing by all of the bereaved families.

"We've got a long way to go before we're going to give this one up."

MH370 disappeared during its March 8 flight from Kuala Lumpur to Beijing. Six Australians were on the plane when it vanished.

Earlier this month, Australia signed a contract worth more than $50 million with Dutch company Fugro, which will use two vessels towing submerged vehicles to scan the search area, which is about the size of Tasmania.

An expert team will work beneath the water surface using sonar and video cameras.

- AAP