Australia has committed up to Aus$89.9 million (US$84 million) towards the search for missing Malaysia Airlines Flight MH370 over two years, budget papers released Tuesday show.

Australia has been leading the hunt for the plane which was carrying 239 people when it disappeared on March 8 en route from Kuala Lumpur to Beijing.

It is believed to have crashed into the southern Indian Ocean but despite a massive air and sea search, including underwater using a US navy submersible, no sign of any wreckage has yet been found.

"The government will provide up to Aus$89.9 million over two years from 2013-14 as part of Australia's commitment to the search for Malaysia Airlines flight MH370," the papers stated.

Some Aus$27.9 million would be given to the defence department to pay for its activities up to June 30, 2014 in looking for the Boeing aircraft, while another Aus$2 million would be spent on the Joint Agency Coordination Centre established to liaise with key stakeholders.

"Further funding of up to Aus$60 million over two years from 2013-14 will be provided to the Australian Transport Safety Bureau for Australia's contribution to the next phase of the search," the papers said.

Australia has been coordinating the search for the plane -- thought to have gone down in its search and rescue zone -- in consultation with China, from where two-thirds of the passengers came, and Malaysia.

Prime Minister Tony Abbott has vowed Australia will do all it can to find the jet which mysteriously diverted from its course, saying he owed it to the families of those onboard to discover what happened.

While the aerial and sea surface searches have been scaled down, Australia is now working on the next phase which will involve using sophisticated equipment to scan the unmapped ocean bed some 4.5 kilometres (2.8 miles) below the surface.

Negotiations are underway to engage contractors to do this work which Abbott has previously said could cost Aus$60 million.