Senior South Australian Liberal Duncan McFetridge has raised significant concerns about the federal budget, describing a host of tough measures as “ambit” claims that should be softened.

McFetridge has offered the frankest assessment yet by a state Liberal of the tough federal budget, laying out particular concerns about the Medicare GP co-payment, deregulation of higher education fees, and changes to unemployment benefits.

In an interview with housing advocacy group Shelter SA on Radio Adelaide, McFetridge said he would be meeting with his federal counterparts to get more information about the details of changes, including a six-month Newstart waiting period for people who lose their job under the age of 30.

“I’m very concerned that people will be left out on a limb,” he said.

“Earning and learning is a nice cliché for politicians to use but you can’t expect people to go and get any job.

“Having said that, I’ve swept up chicken poo and I’ve worked at trash and treasure. I’ve done lots of different jobs to earn some money. So no job is beneath me but at the same time I think if there’s no job available … and when I was younger there were lots of jobs …

“But at the same time the carrot and stick approach has been used a lot in the past. I think we have to offer the carrot rather than the stick.”

McFetridge, whose portfolios including social housing, communities and social inclusion and disabilities, also raised concerns about changes to higher education fees, saying that people should not have to go into “massive debt” to get an education.

“That to me is a concern,” he said.

“All of this is still on the table, open for discussion, and as with any ambit claim with the unions or ministers going into budgets, they are ambit claims and there will be discussions.

“And I have enough faith in my federal colleagues to know that they are realists as well as pragmatists – they are pragmatists, realists and as well as optimists.

“And they know that Australians and South Australians in our case do have limits on what they can pay; do have limits on what burdens they can bear; and so we’re going to have to share the burden, sure, to pay off the debt – but the reality is you do need a safe place to live, you do need a job, and you do need to be able to access health care.”

He said he was pleased that the Federal Government had indicated it was willing to consider changes to reduce the impact of the $7 GP co-payment.

The executive director of Shelter SA, Dr Alice Clark, said the effect of the $7 co-payment would “pale into insignificance if the proposed changes to income support go ahead and people become homeless”.

“If the proposed changes to income support go ahead, and people under the age of 30 have no income for six months, it will be a disaster in terms of their housing,” she said. “People simply won’t be able to pay their rent or their mortgage.”

She said she feared there would be a “massive increase in homelessness”.

“A strategy is needed that includes the following elements: improving the functioning of labour market institutions, reforming the tax and transfer system and maintaining labour market flexibility.

“The critical ingredient though is an education system that better promotes equity and integrated services that assist people with disabilities and those who are homeless.”