The Foreign Office has advised Sir Ian McKellen "not to go to Russia" because of the country's homosexuality laws, according to the actor.
Sir Ian, 74, told the Radio Times: "That's why I can't go... they couldn't protect me from those laws.
"Two and a half hours from London! In the land of Tchaikovsky, Diaghilev, Rudolf Nureyev - gay artists whose sexuality informed their work."
The actor came out as being gay at the age of 49.
Sir Ian McKellen spoke to Lorraine Kelly about his latest projects currently in production, including his first ever sitcom.
The veteran actor said he had just finished filming a comedy about two gay men, and will be reprising his role as Magneto in X-Men.
He said: "It's thrilling, any work would be good, but when the work is fun, or different, it's… I'm having the time of my life."
Sir Ian stars as Gandalf the Wizard in The Hobbit, which is released on DVD at the start of April