Almost 50 jobs have been axed at the Whyalla steelworks with its owner GFG Alliance blaming a prolonged downturn in steel market conditions globally.

The ABC earlier revealed GFG Alliance owed several contractors in Whyalla tens of thousands of dollars.

The steelworks went into administration in 2016, but was bought by the company owned by British billionaire Sanjeev Gupta.

At the time Mr Gupta promised to expand the facility, and now has plans to convert it to producing green iron and steel.

A spokesperson told the ABC the company was taking efficiency steps to reduce its fixed costs.

"That will result in a small number of non front-line staff adjustments," the spokesperson said.

"We are working with those affected to ensure they are supported throughout the process.

"These measures do not affect our steel making or commitment to transition to green iron and steel".

Australian Workers Union acting secretary Gary Henderson said the roles being cut are not "frontline or blue-collar workers".

"The announcement of 48 redundancies at GFG is not good news for the community or the steelworks," he said.

"There's a lot of anxious workers at GFG at the moment."

Whyalla Mayor Phill Stone said the council has been notified of the job losses over the phone and would receive a full briefing from GFG Alliance on Monday.

"We certainly understand there are predicaments at this stage financially," Cr Stone said.

"Everyone would know that GFG would have lost tens of millions of dollars during the blast furnace closure and that has affected their production and obviously their income revenue stream.

"We certainly got a lot of empathy for people that at the moment [are] concerned."

A blast furnace malfunctioned earlier this year, causing the steelwork to be offline for weeks and workers forced to reduce hours and their pay.

Steelmaking at the plant resumed full operations in July.