As McKellen makes the press rounds in support of his return as Gandalf in The Hobbit: An Unexpected Journey, he's also offering his thoughts on reprising Erik Lehnsherr for this upcoming sequel.
"What a gas! I mean, Patrick Stewart and I have just been playing "Waiting for Godot" throughout England and in the West End of London. So, we've stayed in touch. We can't believe it [laughs]. I thought these were Michael Fassbender and James McAvoy's parts, but -- no, no -- we're back. We'll give them a run for their money."
The actor doesn't know too much about the story, despite it being based on a popular comic book run from the early 80s.
"I mean, I haven't read the script, so I don't know how much we've got to do. But, to be back in that world, and for Bryan Singer to be doing it -- with all the success he's had in the meantime -- it's wonderful. Wonderful."
Ian McKellen also commented on Michael Fassbender's turn as Magneto in X-Men: First Class.
"I thought he was exactly that: first class. Excellent. [Laughs] I thought he was better than me. But, we weren't quite playing the same character because he was so much younger than me. And the scope of Magneto, one day a Jewish actor will play it. Clearly, he's Jewish. We first meet him in at Auschwitz and there's scope for all sorts of people to pay Magneto. But, I was just the lucky guy who got to play him first."
X-Men: Days of Future Past was released May 23rd, 2014 and stars Hugh Jackman, James McAvoy, Michael Fassbender, Jennifer Lawrence, Halle Berry, Nicholas Hoult, Anna Paquin, Ellen Page. The film is directed by Bryan Singer.