The chair of NHS Lothian has resigned amid criticism of the board’s handling of the delayed Sick Kids project and just weeks after the chief executive announced he was stepping down.

Brian Houston left over “fundamental and irreconcilable differences” with health secretary Jeane Freeman, the Edinburgh Evening News revealed.

An emergency board meeting is set to take place on Monday, it has been reported.

Departing chief executive Tim Davison said: “It is with great regret that we learn of Brian Houston’s resignation as chair of the NHS Lothian board.

“He has been a fantastic chairman, highly visible in his role and bringing to us a wealth of useful and relevant insight and experience from his previous, highly successful career.

“Over the last seven years he has led the board with intelligent curiosity, rigour and vision, championing an innovation and quality agenda and supporting a kinder, values-based culture.”

Ms Freeman said: “Brian Houston has undertaken the role of chair of NHS Lothian since 2013 and I would like to wish him all the best for the future.

“Arrangements for an interim chair will be announced shortly.

“Work continues to deliver the new Royal Hospital for Children and Young People and the department of clinical neuroscience with senior programme director Mary Morgan overseeing actions to ensure the safe delivery of the site.”