The decision to cast Whitehall, 30, has been controversial.
"If you're an actor, you're an actor," Tovey, 36, told The Telegraph. "The whole thing with Jack playing a gay character ...I'm like, just let him act."
MORE CONTENT AFTER THESE SPONSORS
Tovey was an established actor before he took on his first gay role in the HBO dramedy Looking.
"It's like me saying I could never play a straight character because I am not going to know a straight person's thoughts. I've always been out, and happy with the range of characters I've been offered. I've had the most amazing opportunities," he added.
(Related: After recent split, Russell Tovey says he's "a one-man guy.")