Nigel Edwards will end his 12 years at the NHS Confederation this summer after deciding not to put himself forward for the position of chief executive.

Mr Edwards - who has been acting chief executive since June last year and director of policy since 1999 - is a hugely respected figure in health policy. He was placed 25th in last year’s HSJ100 list of the most influential people in health, a rise of seven places on 2009.

But those close to Mr Edwards believe he is more interested in policy development than in the administration of a large representative organisation.

He will leave the confederation by July to take up new policy research roles at the King’s Fund and Nuffield Trust think tanks.

The confederation hopes to appoint a permanent chief executive by the time of its annual conference, also in July. Mr Edwards has agreed to stay on in his acting role until then.

His decision not to put himself forward for the job permanently comes as the organisation consults its members on its future shape. Questions include what kind of relationship the Foundation Trust Network should have with the confederation. There is also a desire to give the NHS greater ownership of the confederation’s NHS Employers arm, which negotiates pay on behalf of the Department of Health.

The departure of such a respected thinker will prompt concerns about the decline of the confederation and the NHS manager’s voice within policy development.

Mr Edwards said that although the confederation would need to change, there had “never been a more important time” for its role. He said there was now a “critical mass” of policy thinkers in the organisation who could take his place providing policy analysis and input on behalf of its members.

He said: “I’m very confident that if I get run over by a bus tomorrow and [health secretary] Andrew Lansley produces another load of policy, there are plenty of people who will be more than able to dissect that.”