Health spokesman Andy Burnham said the coalition had created queues outside practices and diverted people to A&E.
Tory Health Secretary Jeremy Hunt said Labour’s numbers were wrong and that out-of-hours cover was being extended reports BBC.
The Lib Dems also said Labour’s figures – obtained through a parliamentary questions were out of date.
Mr Burnham announced the analysis as his party unveiled a new poster, which reworks the Conservatives’ “Labour isn’t working” image of 1979 by depicting a huge queue outside a waiting room with the title: “The doctor can’t see you now.”
“On all the indicators it is clear that GP services have gone backwards in this Parliament,” he told the BBC.
Labour has pledged £2.5bn to pay for 8,000 more GPs, guaranteeing appointments within 48 hours.
Mr Burnham said the last Labour government had introduced an extended-hours scheme which, in 2009, funded 77% of surgeries to open on evenings and weekends.
The Commons answer suggested the coalition had reduced extended access funding in England from £3.01 per patient to £1.90 per patient, meaning that – by 2013/14 – 72% of surgeries offered extended hours under the scheme, a reduction of 590, according to Labour’s interpretation.
Mr Burnham told BBC Radio 4’s Today programme that many people were not able to book appointments for days and, as a result, ended up at A&E. “If you are going to have a truly preventative NHS, you have to make sure people can get the right care at the right hours.”
He said he did not blame GPs, who he suggested had been “demoralised” by budget cuts – adding that Labour would also seek to reverse closures of walk-in centres and ensure the non-emergency 111 helpline had more experienced medical staff.