Dr David Geddes, a GP in Yorkshire, wrote in a blog on NHS England's website that practices need to work together to deliver seven-day services.
He said general practice also needs to deliver more integrated community services.
He wrote: ‘Arguably, the current model of primary care is no longer fit for a modern NHS.
'We know increasing numbers of patients are presenting in general practice with multiple long-term conditions, working days are longer and retirement is getting later.
'For many of the population, (myself included) they never see their surgery open. At one event, the chief executive of a local hospital told how a consultant had to cancel his entire clinic, so that he could see his own GP.’
Primary care needs to play an ‘even stronger role at the heart of more integrated out-of-hospital services, delivering better health outcomes, more personalised care, and excellent patient experience, in a sustainable way and as efficiently as possible,’ he said.
‘The elephant in the room is that we need to deliver all this seven days a week.’
Seven-day working will reduce ‘silo working professional isolation’ and increase opportunities to collaborate in 'new and different ways’, he added.
‘Across England, the story appears the same: general practice and wider primary care services are facing increasingly unsustainable pressures, and there is recognition that primary care wants and needs to transform the way it provides services to reflect these growing challenges,’ he said.
NHS England is holding a wide-ranging consultation on general practice, Improving general practice – a call to action, which explores how general practice can transform in response to ‘increasingly unsustainable pressures’. It will run until 10 November.