High-income earners could be hit with higher taxes through the health system to help the Turnbull government pay for the end of a four-year freeze on Medicare rebates for doctors' visits and cover the cost of dumped welfare cuts, a leading economist has suggested.

Speculation surrounded the increases to either the Medicare levy or the Medicare levy surcharge on Thursday after leading Westpac chief economist Bill Evans suggested the government could apply the Medicare levy surcharge to all high-income earners – regardless of whether they had private health insurance – to help pay for the Medicare retreat and $10 billion in junked "zombie" cuts to welfare and higher education.