Cooper replaces James Murray who spent just two months in the post after succeeding Wes Streeting in May.

Following her appointment last night Cooper posted on social media that she was looking forward to ‘working urgently to improve maternity services, to take forward plans for social care and to once again play a part in supporting our National Health Service'.

Cooper added: ‘Most of all I'm looking forward to working with the dedicated NHS staff, carers, healthcare professionals and volunteers on whom we all depend.'

The new health secretary was previously foreign secretary and home secretary under Sir Keir Starmer's Government.

She ran for the Labour Party leadership in May 2015 coming third behind Jeremy Corbyn and Andy Burnham.

Reaction

Welcoming Cooper's appointment, Sir Ciarán Devane, chief executive of The NHS Alliance, said it was important the health secretary provided ‘clarity and continuity' as the NHS goes through major reorganisation.

Sir Ciarán added: ‘We call on the new secretary of state for health and social care to continue with the current direction of travel as any changes now risk slowing progress and diverting attention away from the delivery of better care for patients.

‘Improving health outcomes also requires action to support social care, which is long overdue. We therefore welcome the new Prime Minister's plan to bring about reform of social care, helping to ensure that adult social care services are funded properly and meet the needs of people across the country.'

Sarah Woolnough, chief executive of The King's Fund, said Cooper had been given a ‘very clear mandate' to fix social care ‘at speed'.

She urged Cooper to pick up the ‘stalled' prevention agenda through a ‘health in all policies' approach, adding Burnham's agenda to expand devolution implied a greater focus on ‘the wider determinants of health, from housing to employment, which could be transformational in improving the nation's health if implemented effectively by preventing illness and reducing demand'.

Woolnough concluded: ‘The last administration understood the need to urgently improve how people access and experience health and care services, but with their focus on reducing elective waiting lists, had limited capacity to tackle longer term issues. This new Government has the opportunity to make the tough choices necessary to rebuild for the longer term, creating a social care system and broader health service that is genuinely fit for the future.'

Chair of the Health and Social Care Committee, Layla Moran, said: ‘You cannot achieve reform of the NHS while sidelining social care. Patients cannot be discharged from hospital beds if the right care isn't available, and that means treatments are postponed and longer waits in A&E.

‘We stand ready to work with the Government and Baroness Casey, as soon as her proposals are presented, to make reform a reality. And we look forward to discussing these issues with the new secretary of state at an early stage.'