The chair of the Royal College of General Practitioners (RCGP) has claimed that plans to open GP surgeries seven days a week could cost the government over £1 billion a year.

Speaking at a Westminster Health Forum conference on the government’s controversial seven-day NHS plans, Dr Maureen Baker said: “Independent research commissioned by us into the realistic costs of extending GP hours found that if one in four surgeries opened 12 hours a day, seven days a week it would cost at least £749 million per year, rising to £1.2 billion if that was one in two practices.

“Contrast this with the limited one-off funding of £150 million for extended hours provided through the GP ‘Challenge Fund’ and you see the sort of gap we are talking about.”

The prime minister’s ‘Challenge Fund’ is being used to set up pilot schemes for seven-day services in some areas, but Baker also used her speech to argue that this has not been entirely successful.

“When we look at some examples from the Challenge Fund, we find that 12 hours a day every day is not always in demand for patients. Some of the areas are scaling back opening hours, or as in Canterbury or Richmondshire even cancelling services altogether due to lack of demand from patients and concerns over cost effectiveness.

“There is a demand for Saturday morning services. If you open a surgery on Saturday morning, people will turn up. However, if you open your surgery during Sunday teatime, in a lot of places nobody comes. And we really have to ask, is that the best use of NHS resource, to just be there for the sake of a political soundbite?”

She noted that 60% of surgeons in England are already providing some form of extended opening – and about 1 in 5 are doing so over the weekend. In addition, a GP-patient survey showed that 75% of patients were happy with their GP’s opening hours

Dr Ivan Bennet, clinical director of the Central Manchester Clinical Commissioning Group – one of the areas that has piloted seven-day GP access – said the he disagreed with “practically every single point” that Baker made and asked whether she is happy that 25% of people are not content with their GP’s opening hours.

“It would be great if everybody was happy,” Baker countered, “but it’s never going to happen. 75%, in terms of public satisfaction with services is in fact pretty high. Would we aim for it to be better? Yes […] But with the services we have now, we just can’t. We have a workforce that is stretched as thin as it can be.”