The chairs of the four strategic health authority clusters have been announced and the Department of Health is close to confirming their chief executives.

The Appointments Commission said current NHS Yorkshire and the Humber chair Kathryn Riddle will head up NHS North of England (North West, North East and Yorkshire & the Humber); Sarah Boulton of NHS East of England will chair the NHS Midlands and the East (East Midlands, West Midlands and East of England); and Geoff Harris, currently of South Central, will look after NHS South of England (South West, South Central and South East Coast).

The appointments have been made in principle, but the health authority membership and procedure regulations must be amended to allow an individual to sit on more than one SHA board before they can take effect.

Mike Spyer has been confirmed as chair of NHS London. He has been acting chair of the London cluster since last July.

NHS chief executive Sir David Nicholson is expected to announce the chief executives of the organisations next month, so they can appoint top teams in time to establish the clusters by October.

Sources said Sir Ian Carruthers was expected to lead NHS South of England. The leading candidates for the North are Yorkshire and the Humber chief executive Bill McCarthy and national director of provider development Ian Dalton – previously NHS North East chief executive – although both men are also favourites for national leadership roles on the NHS Commissioning Board.

England’s 10 SHAs are to move into clusters ahead of their abolition in 2013 under the government’s reforms. It is expected they will provide the basis for sub national arrangements of the NHS Commissioning Board.

Sir David said in a statement: “Clustering SHAs will ensure we have sufficient capacity in the system to maintain grip and momentum throughout the transition period.  Moving to four clusters will ensure the best fit between our transition arrangements and the future arrangements for the NHS Commissioning Board, which will be organised across the same geographical areas. I am pleased that these appointments have now been agreed so that we can start to move forward establishing the clusters as quickly as possible.”

The chairs will take up their new positions on 3 October when the clustering arrangement will come into effect.

Appointments Commission chair Anne Watts said: “This is an important first step in establishing the new cluster arrangements.  I would like to thank all of the SHA chairs for the understanding and cooperation they demonstrated throughout this process.”