Greg Hunt says the state government has targets in place to maximise revenue for its public hospitals from privately insured patients that rely on high-pressure tactics to move them over to the private system.

Victoria hit back at the federal government on Monday, accusing Mr Hunt and Prime Minister Scott Morrison of putting the interests of health insurers before that of patients and of staging a “desperate ploy” to distract from their failings in the health portfolio.

The state government says only about 12 per cent of  patients admitted to Victorian public hospitals use their private health insurance and there has been little change in that rate for years.

The state government denies there are any targets in place.

But in a letter to Health Minister Jenny Mikakos, Mr Hunt insists the state is pressuring patients to go private in what amounts to an attempt to privatise public health, with the federal minister saying the “number of patients being treated privately in public hospitals has continued growing at an astounding rate”.

Mr Hunt cited reporting on Sunday by The Sunday Age and the Sun-Herald revealing the extent of the problem with patients from both NSW and Victoria telling of the high-pressure tactics deployed on them in public hospitals.

The federal Liberal minister has sent letters about the problem to Labor-held states Victoria and Queensland, but not to NSW where the Liberal state government faces an election on Saturday.

The federal minister, who will ramp up his attack when he addresses a gathering of the private health industry in Melbourne on Tuesday, wrote to his state counterpart to say he was worried that vulnerable patients were being “targeted aggressively” to be treated as private patients.

“Any pressure upon a patient to be anything other than a public patient is unethical and inappropriate,” Mr Hunt wrote.

The minister’s letter goes on to say that the Victorian "policy" adds to delays in treating public patients, who must sometimes wait twice as long for procedures than their private counterparts, and threatens the viability of private hospitals.

“I have serious concerns that your policy to privatise public hospitals is undermining Medicare principles, taking advantage of patients and putting inappropriate pressure on private health insurance premiums and the private and not for profit hospital sector.”

But Ms Mikakos shot back at Mr Hunt on Monday, accusing him of helping to line the pockets of the insurance industry.

"Scott Morrison and Greg Hunt are putting the profits of the big insurers first and patients last – it’s everything we’d expect from a government who is cutting billions of dollars from Victorian hospitals,” Ms Mikakos told The Age.

“This is just a desperate ploy by the Federal Liberals to cover up the fact their only plans for health are cuts and closures.

“In Victoria, the small rate of patients treated privately in public hospitals hasn’t changed in years.

“It’s time Greg Hunt stopped worrying about lining the pockets of his insurance company mates and reversed the cuts that are putting a strain on our doctors, nurses and patients.”