Australian units of Ford Motor Co and Toyota Motor Corp have already shut down production, and General Motors Corp's subsidiary GM Holden has said it is unlikely to last beyond Wednesday.

A blast on Friday at Esso Australia's Longford major processing plant on the state's eastern coast has knocked out gas supplies to households and businesses in Victoria, and has stopped production from the offshore Bass Strait oil and gas fields.

Holden spokesman John Morrison said the company's Victorian foundry, which produced metal castings for assembly into engines, had all but shut down on Tuesday.

``They will effectively run out of blocks and engine production probably during Wednesday which will effectively shut down the car operations by the end of Wednesday,'' he said.

``Some of thisis a little fluid, but that is our best reading,'' he told Reuters, adding Holden sourced other critical components from Victorian suppliers whose operations also relied on gas supply.

Holden produces about 500 cars and 400-500 engines a day.

Morrison said the production halt would affect about 2,000 workers in Victoria and up to 4,300 at the car production facilities in South Australia, with management currently holding talks with unions about bringing forward leave.

MMAL spokesman Kevin Taylor said Mitsubishi's South Australian production facilities were expected to be able to continue without interruption until the last shift on Thursday.

The company then had a pre-planned production halt through till next Wednesday, taking in a long weekend and a further day off already organised to offset lower than expected exports.

``We are okay today, tomorrow and the current outlook is that we will be okay probably on Thursday as well,'' Taylor said, adding initial concerns had been with components such asbrakes and sound deadening padding.

He said Mitsubishi, which produces about 250 units a day, faced a plant shutdown if the gas supply crisis continued until the end of next week as Victorian authorities have warned.

``If that is the case, you would think at some stage next week we are going to run into a real problem,'' he said.