Ministers have warned that hospitals will stick "two fingers up" at the new rules which try to stop excessive "tax on the sick" parking charges.
Relatives of gravely ill patients, patients with disabilities, those with frequent appointments and staff working shifts must be given free or cheap parking under new Department of Health guidelines issued to English hospitals.
Charges have been largely abolished altogether in Scotland and Wales yet in England, 79 per cent of hospitals continue to charge - sometimes up to £500 per week. Parents with premature babies are having to pay on average £32 per week to park their cars.
However, ministers during a House of Commons debate weren't convinced that hospitals would abide by the guidelines and called for the Department of Health to have a "plan B" in place should this happen.
Birkenhead MP Frank Field said: "We know from our local areas that some hospital trusts will gently put two fingers up to what the Secretary of State says.
"I very much hope that when the Minister replies he will say what plan B is for those hospitals that continue to charge excessively those who need to continue to visit their relatives in hospital."
Some ministers went even further and called for abolition of hospital parking charges in England and branded them a "tax on NHS treatment".
Telford MP David Wright added: "I believe that hospital parking charges should be abolished. Some people have expressed the concern that people will overflow park in hospital parking areas.
"Tickets could still be issued to ensure that parking spaces are controlled, but it could be made free. The House should push the Government and the Opposition to make a commitment to abolish parking charges at hospitals in the medium to long term."
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