A stand-off between crew members of an oil tanker in Tasmania and the ship's operator has been referred to the Industrial Relations Commission.

Caltex Australia does not need the tanker Alexander Spirit to transport fuel between domestic ports anymore, and plans to replace the Australian crew with foreign workers on a new international route.

But the crew is ignoring instructions to sail to Singapore, worried that they will be sacked when they get there.

Ian Bray from the Maritime Union of Australia says members want to know what will be done about their redundancy entitlements and repatriation.

The operator – TeeKay Shipping - says the crew is engaging in illegal industrial action, and will argue as such in the Industrial Relations Commission.

Federal Employment Minister Eric Abetz says he wants to see the dispute dealt with quickly.

“The circumstances must be very difficult for the workers,” he said.

“Job security is an important issue for anybody, especially in Tasmania where we've got a situation of, still, relatively high unemployment.

“Whether the employer is right or wrong, whether the maritime union is right or wrong in this dispute, is for the Fair Work Commission to determine.”

Mr Abetz rejected suggestions that new Government legislation was at fault.

“Nothing has changed ... in relation to cabotage,” he said.

“It is a real issue when it costs more to ship sugar from Brisbane to Melbourne for the confectionary industry than it does to buy the whole lot and ship it from Thailand to Melbourne.

“Some of the local shipping is pricing itself out of the market ... the legislation that is before the Parliament is not impacting as we speak.”

Independent Tasmanian senator Jacqui Lambie called on the LNP to guarantee that a $33,994 ­election donation by Caltex, ­recorded on the Australian Electoral Commission website, had not influenced the Government’s recent Shipping Legislation Amendment Bill.

A spokesperson for Mr Abetz said ­political donors did not dictate Coalition policy.

Tasmania's Opposition Leader Bryan Green supports the industrial action, saying it was needed to protect local jobs.

“[We have] Caterpillar jobs being lost from here to a factory in Thailand, this is not too dissimilar,” he said.

“If we don't make a stand when it comes to protecting our well paid jobs against jobs that are effectively people being paid nothing, then what are we doing as a country?

“We've got well paid jobs that are being lost, being replaced by people on very low wages.

“I think this is an issue that should galvanise the country to make sure that we protect these people, the jobs, and allow the whole country to understand just how important it is to stand up for them.”