An accountable officer has been appointed across eight clinical commissioning groups in London, covering the most populous patch of any chief officer.

Mark Easton has taken up the role across north west London, covering the boroughs of Westminster, Kensington and Chelsea, Hammersmith and Fulham, Ealing, Harrow, Brent, Hounslow and Hillingdon.

It is a single sustainability and transformation partnership area, although it is not yet known whether Mr Easton will be the STP lead.

There were previously two chief officers across this patch – Clare Parker covering the five inner London CCGs and Rob Larkman running the three in outer London. Neither applied for the single accountable officer role, although Mr Larkman covered the role for the past month.

The north west London CCG role is thought to be England’s biggest NHS commissioning job by population outside of NHS England. The population is about 2.4 million.

Other large populations under a single CCG accountable officer include North East London (about 2.1 million); Kent and Medway, where Glenn Douglas is taking on the role across a population around 1.7 million; and Birmingham and Solihull CCG, whose chief is Paul Jennings, covering 1.3 million.

Mr Easton joins from the north central London CCG cluster, having worked before that on the south east London STP. Previously he has held a strategy role at Barts Health Trust and was chief executive of Barnet and Chase Farm Hospitals Trust.

Amended at 3.30pm on 31 May to mention Kent and Medway’s shared chief officer.