The Bill, which had its second reading in parliament last week, will make it more difficult for GPSIs to be registered to perform their role, said deputy director of NHS Employers Sian Thomas.
The Bill includes recommendations made in a White Paper published in February on the future of professional regulation. After being relicensed as a GP, GPSIs will also need specialist recertification with standards set by the relevant royal colleges and the GMC.
Ms Thomas said: 'What we need to do is make sure that when people become GPs they can be revalidated in a sustainable way.
'GPSIs are experienced and where they work well, they work well in a local tailored support mechanism with a hospital specialist, and that can't be sustained across the NHS.'
There are more than 1,700 registered GPSIs in the UK. They have been anticipated to play a vital role in the move of secondary care into the community through practice-based commissioning, and have featured heavily in DoH pilot schemes into moving care closer to home.
But Ms Thomas said: 'We believe that what patients want is hospital specialists who are on the register as specialists.
'We want GPs to be doing the best job they can possibly do in primary care as GPs.'
But GPC chairman Dr Laurence Buckman said preventing GPSI revalidation would go against government policy.
'I can't immediately see why it's more difficult for them than anyone else,' he said. 'Revalidation has not been negotiated.'
Answering questions in the House of Commons last week, health minister Ben Bradshaw said: 'The development of GPSIs has expanded the range of options available to local commissioners.'
Professor Ram Dhillon, member of the Association of Practitioners with Special Interests and an ENT consultant at Northwick Park hospital in north London, said more GPSIs were needed if the government goal to move secondary care into the community was to be achieved. 'The aim wants to be that every GP in the next 10 years becomes a GPSI,' he said.
Comment below and tell us what you think