Timothy will become CEO of the Portman Group, an industry-funded organisation promoting responsible alcohol standards, on 19 June.
He has been at Tesco in a variety of corporate and public affairs and comms roles for the past 10 years, working across the UK, Brussels and Asia. He has also worked closely with the CBI and the British Retail Consortium.
Former Portman Group CEO Henry Ashworth stepped down in December 2016 to take up the post of President of the International Alliance for Responsible Drinking.
Timothy said: "It is clear to me that the industry’s approach is having a positive impact with falling levels of alcohol misuse across the UK. We will strive to ensure that continues to be the case and I look forward to working closely with Portman Group members, and partners from all sectors, to help support these positive cultural changes and to tackle alcohol-related harms."
Sir Martin Narey, chairman of the group, said: "I am delighted that John is joining us as we look to strengthen our efforts to tackle alcohol-related harms and foster a balanced understanding of alcohol in our society."
Tesco's new corporate affairs chief, Jane Lawrie, joined in October, just days before the supermarket hit the headlines in a Brexit-based pricing dispute over Unilever.