He highlighted winning the URC last season as “a phenomenal achievement” but suggested “the future is definitely bright in the second row” at Glasgow, with Scott Cummings, Max Williamson, Alex Samuel and Jare Oguntibeju competing for places.
Gray has amassed 79 Scotland caps and featured once for the British and Irish Lions during their 2013 tour of Australia.
At pro-team level, he also won the French Top 14 final with Toulouse.
Glasgow head coach Franco Smith added: “Richie has been a fantastic servant to this club, both on and off the field.
“When I first came in, he very quickly adapted to the intensity of our training sessions as well as also adapting elements of his game.
“It will be sad to lose him, but this is a massive opportunity for him at this stage of his career. I know from experience what an opportunity like this means as you’re coming to the end of your career and I’m very proud of the way he has gone about his business.”
Callum Simpson halted Steed Woodall to defend his British and Commonwealth super-middleweight titles on an emotional night in Shef
Brighton head coach Fabian Hurzeler was delighted to see his side get back to winning ways as they triumphed 4-0 at Norwich to reach the fourth round of the FA
Chelsea head coach Enzo Maresca praised a “serious, professional” display from his team after they romped past League Two Morecambe in the FA Cup third roun
Stewart started his role on 16 December after Rangers went six months without a chief executive following the departure of James Bisgrove to Saudi Arabia, while