Baron Tim Bell, who was an advisor to former prime minister Margaret Thatcher, told talkRADIO's George Galloway on Friday night that he doesn't think Theresa May is as radical as Mrs Thatcher was.
It followed newly-released official files, which showed that the former Conservative prime minister secretly continued to pursue politically explosive plans to dismantle the welfare state even after ministers thought they had been killed off by a cabinet revolt.
"I don't think (May) thinks as deeply as Margaret does about these things, and I don't think that everything she tries to achieve has been inhibited by our obsession with a free health service."
Baron Bell said the UK has a health service that we can't afford.
"We offer a health service, social care and a pension to millions and millions of people that we can't afford."
He also said his view of Mrs Thatcher is "absolutely, completely undimmed" after the release of the papers.
"I cannot think of any problem this country faces, particularly Brexit, which she wouldn't have faced completely in the jaw and done what is necessary."