GPs attending the UK's biggest family doctor conference are being encouraged to earn extra money treating private patients.
Medics can earn £50 to £60 per hour - or up to £90,000 a year if they work full-time equivalent hours - on top of their NHS salary by offering consultations to patients on their smartphones.
The cash is being offered by the firm Babylon to GPs who want to work "flexibly" from part-time to full-time. Doctors are told they can work from home or their usual workplace.
The Royal College of GPs (RCGP) has accepted thousands of pounds from Babylon to put recruitment flyers in around 1,500 delegate bags at the RCGP annual conference in Harrogate.
As bronze sponsors of the conference, Babylon has also paid for its logo to appear on the conference handbook and website.
It comes just a day after RCGP chairwoman Professor Maureen Baker said NHS doctors were under intense pressure.
She said GPs were "worried about making errors because they are so overwhelmed with work. This is a serious threat to patient safety."
Babylon works by offering patients unlimited private GP consultations for £4.99 per month or for a one-off appointment fee of £25.
Patients can get access to one of 100 doctors for webcam or text message consultations seven days a week from 8am to 8pm.
Katherine Murphy, chief executive of the Patients Association, said GPs were often trying to tackle long waiting lists but added: "What is disconcerting about this situation is that private firms are allowed to advertise positions at a conference of the RCGP.
"What this means is that NHS doctors are being targeted to give up their role working for our NHS and instead work for private companies, which I think most patients would consider unethical. When the NHS is so desperately short of GPs, how can this be right?"
The RCGP accepts sponsorship money from a wide range of firms for its conference, including pharmaceutical companies Pfizer and Novartis.
In 2014, the most recent figures that are publicly available, bronze sponsors such as Babylon paid the RCGP £11,500 plus VAT.
Dr Mobasher Butt, global medical director of Babylon, said: "As a GP, I see doctors across the country working in public, private and voluntary organisations.
"At Babylon we work with NHS and private patients. Our GPs are often juggling family and professional commitments, and value the flexibility that we offer.
"Without this flexibility, many would not work additional sessions to their NHS work, which in effect is actually increasing our total national GP capacity.
"All of our GPs carry out face-to-face practice, mostly in the NHS, and Babylon provides them with a much-welcomed addition to their portfolio of work.
"We have an excellent relationship with the RCGP, having met members of the RCGP council to discuss our service in detail, which they found impressive.
"Many of our GPs, including myself, are RCGP members and Babylon is proud to support the College."
Despite Babylon flyers telling GPs they have the "freedom to work from home or your workplace", Dr Butt said "all of our GPs work from home and we do not recommend working from their NHS practice".
A spokeswoman for the RCGP said: "The RCGP exhibition is a commercial venture that generates income for the College's charitable work.
"It showcases latest developments in general practice and all exhibitors go through a rigorous process before they are allowed to take part.
"The decision to allow Babylon to become a bronze sponsor at this year's conference was taken on the basis that it is an emerging digital healthcare company."
She added: "At the moment, general practice in the UK is struggling, and we need to pull out all the stops to recruit as many GPs to the NHS as possible, and retain existing ones.
"But that is not to say we are in a position to close the doors to opportunities for our members.
"Babylon's presence at the annual conference is in line with the College's sponsorship policies. Due to commercial confidentiality we are unable to disclose further details of the sponsorship."
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