Australia’s national security has been “profoundly compromised” and manufacturing jobs put at risk by the closure of Victoria’s Altona oil refinery, the federal opposition warns.

ExxonMobil told workers at the oil refinery on Wednesday that it was no longer “economically viable” to operate the plant.

At least 350 staff are expected to be affected by the closure of the 72-year-old site, which will be turned into an import terminal to ensure ongoing fuel supply for the state.

“The Altona refinery will remain in operation while transition work is undertaken to ensure continued reliable fuel supply for our Mobil customers,” the company said in a statement.

Energy Minister Angus Taylor said the development was “extremely disappointing”, adding the federal government would work with the Andrews government to ensure workers were supported.

He said the plant closure would “not negatively impact Australian fuel stockholdings” despite the closure meaning Australia would now only having two refineries.

The comments have not convinced deputy Labor leader Richard Marles, who lashed the government over the “crisis”.

“If we do not refine fuel in this country, we are far more exposed internationally and our national security is profoundly compromised,” Mr Marles said.

“As a matter of our safety we need to be able to have the capacity to refine fuel in this country.”

The ExxonMobil closure is the second oil refinery closure announced in five months, with BP last year deciding to shut the Kwinana refinery in Western Australia.

The Maritime Union of Australia has slammed the Morrison government’s $2.5bn fuel security package – which aimed to protect industry and motorists from future higher fuel prices – saying Viva Energy plant in Geelong had been the only refinery to sign up.

“Even before these refineries close, more than 90 per cent of Australia’s refined fuels are coming from overseas, leaving the nation seriously exposed to any crisis that impacts on maritime supply chains,” spokesman Jamie Newlyn said.

“The federal government should insist that if the Altona refinery closes, ExxonMobil must create a fleet of Australian-registered tankers to carry fuel to Australia and transport it around the coast.”

But United Workers Union national secretary Tim Kennedy said Australia’s domestic labour market had been hollowed out so extensively that Altona workers would not have equivalent jobs to move into once the site closed.

“The federal government needs to invest in just transition and quality jobs of the future,” Mr Kennedy said.

Nationals Senator Matt Canavan told Today that Australia’s economy relied on industries that emitted carbon.

“We’ll be down to two oil refineries, but at least we’ll be closer to net zero,” he said. “This is madness, it has to be stopped.”

A ExxonMobil Australia statement said an extensive review of its Altona operations considered “the competitive supply of products into Australia, declining domestic crude oil production, future capital investments and the impacts of these factors on operating earnings”.

Chairman Nathan Fay thanked the federal government for the “significant support” offered to Altona – which had been receiving JobKeeper – and other refineries.

“ Our decision to convert our facility to a terminal is not a reflection of those efforts,” Mr Fay said.

Originally published at news.com.au