Keith was recruited to help set up and run a new trade association, originally called OFI UK, to tackle a number of big issues facing the industry at the beginning of the 90s.
The trade association will now start the process of recruiting a new chief executive and the role will be advertised shortly.
“The OATA Directors are very sad that Keith will be leaving us but we understand that he considers it’s the right time to hand over the reins after a quarter of a century protecting and promoting the industry,” said OATA chairman Mark Evenden.
“We’ll certainly miss him but we have known this was on the cards so we’re now planning for the future. We’ll be advertising the role in the very near future and Keith will be with us as we plan a smooth transition for the new chief executive.”
Keith added: “After 25 years at OATA I feel it’s time to move on and do other things. It is purely down to the passage of time.
“It’s a great opportunity for OATA to take forward its development and increase its ability to promote and protect its members and the industry as a whole.
“I have a period of notice to serve so I’ll be around for some time and I hope I’ll continue to receive the tremendous support that I have to date and I will continue to do my best for OATA.”