NHS chief executive Sir David Nicholson has said he doubts whether health secretary Andrew Lansley’s plans to implement GP commissioning can be achieved by April 2012.

Giving the closing speech to the NHS Confederation conference in Liverpool last Friday, Sir David said he doubted the reforms would be ready for full implementation by April 2012, the date Mr Lansley has told officials he wants.

Sir David said “even the most optimistic people won’t say we will get this system up and running” by April 2012. He also warned he thought it was a mistake to set a timescale for introducing the policy.

He said: “I think it’s dangerous to put a date of that kind of nature [on it].”

He said the success of the policy would depend in part on negotiations with the British Medical Association and that naming a date by when the government wanted the system in place would only empower the BMA in its negotiating position.

Sir David added that, on a scale of one to 10, even the best GP practice based commissioners were “only about a three” in terms of the quality of their commissioning.

Sir David was speaking the day after Mr Lansley had told the conference that he acknowledged the need for new accountability arrangements to oversee GP commissioning, while also saying there was no benefit in delaying implementation of the policy.

Mr Lansley said: “I have been with GPs who say they are ready to go now. There is no merit in making these changes take a long time. There is every merit in knowing what we need to do and doing it quickly.”

But HSJ has been told the Treasury has also questioned Mr Lansley’s desired timescale and has slowed the implementation of the policy.

The Treasury has written to the Department of Health outlining its concerns about the accountability arrangements for transferring responsibility for the majority of NHS spending to GPs.

Sir David confirmed the Treasury “was concerned about financial performance” under the policy. He added: “So am I”. He said the NHS had “fought hard” to recover its “financial grip” since the deficits of 2005-06 and he was not going to allow that to be put in jeopardy.

He said: “Never mind the Treasury, they [ministers] have got to get past our tests first.”

Sir David acknowledged the eventual implementation of the policy would lead to job cuts within primary care trusts.

He said: “We need to be realistic. There is a significant management cost saving [to be made]. Some people are going to lose their jobs in this time. Do not give people false hope.”