His departure comes just one week after Mr Tobin – who had been with the Celesio group for more than 10 years – told Lloyds employees that 190 “commercially unviable” branches of the multiple would have to close or be sold.

Celesio UK said the remaining members of its board would manage the business “whilst a successor is sought”.

Brian Tyler, chairman of the management board of McKesson Europe – which owns Celesio – said Mr Tobin had “built a strong leadership team for Celesio UK”, and added “his warm and engaging personality made him many friends across community pharmacy and beyond”.

“I am grateful for the dedication that Cormac has shown over the last few years and his leadership through an ever-changing external environment,” Mr Tyler said.

Read C+D's exclusive interview with Cormac Tobin from earlier this year.