Patients would be legally entitled to see their GP within seven days – or 24 hours in urgent cases – under plans drawn up by the Lib Dems.
This right would be enshrined in the NHS constitution, meaning the Government and health service would have a duty to observe it, the party said.
The move would be achieved through increasing training places for GPs, changing pension rules in a bid to curb early retirements, and encouraging people to return to the health service through a recruitment drive.
It comes as the Lib Dems are warning of a “stark postcode lottery” in the GP system, with wait times of more than two weeks for one in four appointments in some parts of the country.
The policy granting people a legal right to see their doctor within seven days is set to be announced by leader Sir Ed Davey in a speech at the weekend.
He claimed “far too many” people are enduring an anxious wait for care, warning of potential missed or delayed diagnoses as a result.
Some people may also turn in desperation to already “overstretched” A&E departments as they wait to be seen, he said.
The Lib Dems said research commissioned from the House of Commons Library showed there were five million GP appointments in England with wait times exceeding 14 days in September 2022.
This represented 17.9% of the total, the party said – a significant rise on 11.9% at the start of the year.
The Tories promised to deliver 6,000 more GPs at the last election in 2019, but the Lib Dems claim the number qualified has actually fallen by more than 500 since then.
“Patients are suffering from years of neglect under the Conservatives, who have repeatedly broken their promise to recruit more GPs,” Sir Ed said.
“Liberal Democrats would guarantee people a right to a GP appointment within one week, or within 24 hours if they are in urgent need.
“This would reduce pressure on our hospitals and paramedics, saving crucial time and money elsewhere in the NHS.”
The party is urging the Government to recruit an extra 8,000 GPs to deliver 65 million more appointments each year.
It is also calling for a 24/7 GP appointment booking hotline, so people can schedule help whenever they need it.
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