The characters, played by Matt LeBlanc and Lisa Kudrow between 1994 and 2004, flirted with each other throughout the series, with Joey even proposing at one point as he thought Phoebe was pregnant.
However according to Crane, who co-wrote the show with Marta Kauffman, the pair were never supposed to become more than friends.
“It all would have been too tidy and too complete,” he told Metro. “When your goal is to keep the six character in stories together, it would be really easy to go down that road but I think we all felt it would be a mistake.”
As fans of the show will know, Jennifer Aniston’s Rachel and David Schwimmer’s Ross ended up in a relationship after many romantic highs and lows, while Courtney Cox’s Monica and Matthew Perry’s Chandler tied the knot and moved away to the suburbs to start a family.
Crane is currently in London for the latest FriendsFestive, which runs until 21 December.