Canberra – The long-awaited, multi-billion dollar oil and gas deal between Australia and East Timor will soon be presented to cabinet for a final tick of approval.

Foreign Minister Alexander Downer said all major elements of the deal had been agreed by both countries, but some last minute fine tuning was needed.

Under the deal, East Timor will drop permanent maritime boundaries covering the oil and gas rich Timor Sea for 50 years. In exchange, it will receive a share of revenues estimated to be worth up to $5 billion from the Greater Sunrise oil and gas field.

East Timor will also receive 90 per cent of revenues from the Joint Petroleum Development Area, worth more than $10 billion.

"Officials are working on the fine tuning of some minor aspects of the agreement," Mr Downer told parliament. "But this is an agreement that will be considered by the two cabinets [of both countries] soon. It's important to make this point that this is at least a draft agreement which safeguards Australia's sovereign interests while being generous to East Timor and that is what we have wanted to achieve."

Talks on the agreement have dragged on for more than a year and stalled repeatedly over the disputed maritime boundary between Australia and East Timor. Australia has been accused of playing hardball over the resources – worth an estimated $41 billion.

Melbourne businessman Ian Melrose also bankrolled a series of TV advertisements to try and embarrass the Australian government over the deal.

Mr Downer said critics like Mr Melrose were trying to pursue their own personal campaigns. "I think on this issue it's important that people examine the facts and on acquaintance with the facts I think they'll see that this has the potential to be a very good, mutually beneficial agreement," Mr Downer said.

East Timor's Foreign Minister Jose Ramos Horta agreed and praised Mr Downer and Prime Minister John Howard for their roles in the talks. "Without them and the honest and firm leadership of (East Timor's) President Xanana Gusmao and Prime Minister Mari Alkatiri, we would not be where we are today; on the cusp of securing for the people of Timor-Leste the fairest agreement possible with respect to the Greater Sunrise area," he wrote in an article published in The Age newspaper.

"Our side's approach has been realistic and pragmatic so that we have safeguarded our sovereignty and our security, while allowing us to reach the best overall agreement that enhances our national interest."