GPs must realise the family doctor service is facing a shake-up and get involved, a health expert has said.
NHS Direct is one of the newer healthcare services
Professor Chris Ham urged doctors at the British Medical Association's GP conference not to fight the changes.
He said patients would in future be able to choose the NHS Direct helpline and walk-in centres, traditional practices or super-surgeries.
But GPs rejected the government's push towards larger practices and warned small practices were under threat.
The government is looking to set up so-called super-surgeries, offering a range of services such as minor surgery, heart checks and diabetes clinics which have previously carried out in hospitals, across the country.
But doctors are concerned such changes will be at the expense of practices with one or two GPs, which they say provide the personal care that patients prefer.
Patients can already call NHS Direct for health advice, or visit walk-in centres for minor problems.
Professor Ham, a health policy expert at the University of Birmingham, said GPs had to expect the government would look to change primary care in its third term.
He said: "Super-surgeries are shorthand for much more integrated services. We need to walk towards that."
He said there were advantages as well as disadvantages to super-surgeries.
"They can reduce variations and provide wider services - outpatient care, diagnostics.
"I see a future (for them). Either we do it ourselves or other people come in and do it for us."
But Dr John Dracass, a GP in West Hampshire, said the government plans would lead to the fragmentation of primary care.
He said it was not what patients wanted, and urged ministers to build upon the current system and not "destroy it".
And Bedfordshire family doctor Peter Gledhill said small practices were the "cornerstone" of the GP system.
He said in towns and cities they were the choice of people who would feel lost in a big practice.
And he added in rural areas they were often the only choice for patients.
"The government should look beyond the economies of scale (of big practices)."