But the union supporting them has ruled out broader industrial action over the dispute, which has led 18 crew members to stage a sit-in on the Tandara Spirit for the past 15 days.

The dispute started on November 6, when the ship's owner Viva Energy ordered the crew to sail to Singapore, where they would be made redundant and the ship, one of only five Australian-crewed petrol tankers in operation, would be returned to its owners.

Viva Energy said the Tandara Spirit, which was mostly used to transport fuel from Geelong to Adelaide, was no longer needed.

The company owns and operates Shell's former Geelong refinery.

Crew member Kevin Millar said that on November 7 the crew were notified that Vietnamese tanker Vinalines Galaxy had been chartered to collect cargo already designated for the Tandara Spirit.

Mr Millar, a crew member since boarding the then new ship in Korea seven years ago, said on Friday the crew was receiving regular supplies and would hold out until Viva Energy agreed to discuss their jobs and fuel security.

"We've got food, supplies, we're quite equipped, we've got good living conditions - that's Australian standards, not like the Vietnamese one, which I understand has been pulled up by AMSA (Australian Maritime Safety Authority) over their living conditions," he said.

"We need answers, we need consultation, and I think the community at large - the Australian workers - all need answers.

"We'll stay on the ship until all the answers are on the page."

The Maritime Union Association's assistant national secretary, Ian Bray, echoed the crew's demand for consultation with Viva Energy, and Teekay, the crew's employer.

"The union is very sympathetic to the workers on board, not only about their jobs but also their unanswered questions about fuel security and the future of Australian shipping around the Australian coast," Mr Bray said.

"We now import 91 per cent of Australia's fuel task, so in times of economic crisis when ships are laid up, in times of acts of terrorism, acts of war, shipping lanes being closed, we're not guaranteed that supply.

"The second part of that is once we lose control of how it's regulated, it probably has a direct affect on consumers at the bowser, where we're subject to price-gouging."

Mr Bray said the union would not sanction broader maritime industrial action, but did not rule out the possibility of other ships' crews joining the protest.

"There may be other ships whose futures and the crews on those ships futures, their livelihoods, come under jeopardy and the same questions will no doubt be asked," he said.

Teekay, the ship's operator, confirmed it had been redirected to Singapore to be returned to its owner.

"While no decision has been made regarding the continued employment of the crew, it is likely that 36 employees will be made redundant," a company spokesman said in a statement.

"Should the crew be made redundant they will all receive their entitlements under their respective enterprise agreements."

A Viva Energy spokeswoman said the company had little need to export fuel from Victoria to other states, and therefore the Tandara Spirit was not being replaced.