The Morrison government is being urged to apologise to the thousands of Australians who suffered distress because of its failed robodebt scheme.

The government announced on Friday $720 million will be refunded that had wrongly been sought for around 470,000 welfare debts thrown up by the scheme because of faulty income assessments made by the Australian Taxation Office.

An estimated 373,000 Australians received computer-generated debt notices from Centrelink.

The government has promised to repay anybody who had complied with an unsound notice.

However Opposition government services spokesman Bill Shorten said people won’t get their money back until July, money the government was never entitled to take.

“There’s been a lot of harm done here and the class action isn’t over,” he told the Nine network on Saturday.

“They’re now facing a court trial courtesy of the class action … so when the ministers have to appear in court – that’s what’s motivating them.”

• Victims furious as government backs down on robodebts

But cabinet minister Keith Pitt believes there is nothing to apologise for when conducting oversight of a large government program.

“The biggest issue that gets raised with me and my office on a regular basis is from Australians who are concerned about taxpayer support that perhaps has been provided inappropriately or for people who are making a claim that is not quite correct,” he told Sky News.

Liberal backbencher Fiona Martin also defended the actions of government Services Minister Stuart Robert, saying he was first aware of the problem in November 2019 and immediately paused the scheme.

“The issue has now been addressed … he has acknowledged that the ATO data was not sufficient and he is making steps to rectify it,” she told ABC television.

But NSW Labor senator Tim Ayres is unhappy about the timing of Mr Robert’s announcement, coming shortly after Prime Minister Scott Morrison had finished a major press conference where he had made no reference to it, avoiding scrutiny of assembled journalists.

“Last Friday was an announcement late on Friday afternoon about a $60 billion error in the government’s JobKeeper scheme,” Senator Ayres told ABC television.

“This Friday afternoon it is a $720 million bungled robodebt scheme. I really worry about what next Friday afternoon is going to bring.”

-with AAP