The management title Health Service Journal used the 2009/10 financial performance of 190 practice-based commissioning (PBC) consortia across 33 PCTs to predict that, when GPs take on £80 billion in 2013/14, they will create a deficit of £2 billion.
It is widely accepted that PBC failed to achieve its aims, with the DoH's primary care czar David Colin-Thome having described it as a corpse last year.
Mr Lansley responded to the story by saying his proposals 'are not the same as PBC'.
'The whole point is that general practice should be making real decisions, with real implications for their patients' care, within real budgets,' he said.
'The Health Service Journal story is therefore nonsense.'
The health secretary was also forced to defend the policy as Muscular Dystrophy groups said GP commissioning would be a disaster for children with rare illnesses.