Humber Health Partnership is formed of Northern Lincolnshire and Goole NHS Foundation Trust and Hull University Teaching Hospitals NHS Trust, which sits at the bottom of the acute trust league table.
The letter to group chairman Alan Downey, which was seen by the BBC, expressed concerns over the future of local services.
It stated: ‘We regret to inform you that we have reached the point where we have no confidence in the group chief executive and the current executive leadership's handling of the Humber Health Partnership group structure, and its impact on NLAG services.
‘We wish to be clear that this letter does not express no confidence in you as chair, nor in the non-executive directors individually.'
Former health and social care secretary Wes Streeting said the turnaround of Hull University Teaching Hospitals NHS Trust was under way in April 2026.
Hull Royal Infirmary is among 40 new and expanded urgent care sites across England as part of Government efforts to tackle corridor.
‘Widespread improvements' were been found in in end-of-life care services at Northern Lincolnshire and Goole NHS Foundation Trust hospitals by the CQC last month.
A spokesperson for NHS Humber Health Partnership said: ‘The chair and non-executive directors have considered the correspondence, and the group chief executive and executive team continue to have the full confidence and support of the board.
‘A significant part of the correspondence relates to the future organisational arrangements for NLaG, which are already being considered through the organisational review, supported by NHS England with independent input from Carnall Farrar. Consultant colleagues have contributed to that work, including by putting forward their own proposals for consideration.
‘The review is expected to conclude in the coming weeks and will then be considered by the boards.
‘The chair has responded directly to the colleagues concerned. Our focus remains on completing the organisational review and reaching decisions based on its conclusions in the interests of our 19,500 colleagues and the 1.8m people we serve.'
