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Labour MP Julie Cooper's bill to exempt carers from parking charges was stymied by Tory MPs and is unlikely to become law.
Ms Cooper said the charges were "one extra penalty" carers did not need.
Social Care Minister Alistair Burt said local hospitals should make their own decisions but should try to reduce the "cost burden" on carers.
Mr Burt and backbench Conservative MPs made lengthy speeches in an attempt to kill Ms Cooper's bill by using up the Commons time allotted to it, a tactic known as filibustering.
Philip Davies, who spoke for 90 minutes, said Labour MP Julie Cooper's bill was "unnecessary" and his colleague, David Nuttall, warned it could divert money away from frontline NHS services.
Conservative MP Christopher Chope extended the Tory filibuster by more than 30 minutes with his speech saying the Labour MP's plan would be difficult to police.
The level of charges varies between hospital NHS trusts, but the average cost in England is Â£39 per week and in London it can be about Â£130 per week.
Introducing her bill, Ms Cooper told MPs hospital parking charges placed an "unfair financial burden" on carers, and represented "one extra penalty".
She said she had cared for her own mother when she was in hospital.
"Each night when I left tired and distressed I queued up to pay for my parking," she said.
"At that time it was costing me Â£40 a week. On one of those days driving out of the car park, it occurred to me that I was lucky because I could afford to pay this charge and I went on to reflect on the matter and I thought what about those people who can't afford to pay."
Her bill would place a duty on health authorities to exempt carers who are in receipt of, or have an underlying entitlement for, Carer's Allowance and those who have been certified by a clinician as providing, or intending to provide, substantial care on a regular basis.
Hospital parking policies are set by individual NHS trusts in England.
Mr Burt said carers were "unsung heroes" but that it was up to individual NHS trusts to decide how they structure their parking charges.
"A one-size-fits-all central policy is not appropriate for car parking," he said.
"However we understand the cost burden on carers that might have to make frequent visits so we encourage hospitals to look at the discounts they can offer."
MPs have the chance to continue debate on Ms Cooper's bill on another day, but the measure is now unlikely to become law.
Department of Health guidelines on hospital car parking charges suggest concessions should be available for carers with relatives who are gravely ill or who have an extended stay in hospital.
They also say concessions should be offered to people with disabilities and NHS staff whose shift patterns meant they could not use public transport.
A Downing Street spokeswoman said the government had already produced guidance to hospitals on who should be exempted from parking charges but said it was for trusts to decide what is appropriate in local areas.
Hospital parking charges in Scotland and Wales were abolished in 2008. They have also been axed in most hospitals in Northern Ireland and for those that remain, patients with many long-term conditions are exempt.
Three car parks in Scotland, operated under Private Finance Initiative contracts, still have charges and four hospitals in Wales continue to charge, but have been told to abolish these once contracts with private parking firms end.
Katherine Murphy, chief executive of the Patients Association, said the "exorbitant fees" charged for hospital parking could cause "great amount of distress" to patients and their families.
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[NEXT_CONCEPT]
The government has encouraged hospitals to offer discounted parking for carers as it rejected a bid to change the law.