The former nurse oversaw the merger of WNL into England's largest ICB, serving 4.5m residents across 13 London boroughs earlier this year.

She said: ‘I am delighted and excited to have been appointed chief executive of NHS West and North London.

‘We have made significant progress in bringing together our new organisation, with a new remit, new responsibilities and focus. 

‘My immediate priority is on building an integrated care board that is ambitious, high performing and absolutely dedicated to improving the lives of the people and communities we serve. This will be powered by a culture of openness, inclusion and compassion that represents everything positive about our communities in west and north London.'

Fisher was previously chief executive at Ashford and St Peter's Hospitals and at West Hertfordshire Hospitals NHS Trust.