James McAvoy felt like he was filming a sex scene on his first day on the 'X-Men: Days of Future Past' set.

The 35-year-old actor plays a younger version of Charles Xavier, who was first portrayed by Sir Patrick Stewart in the original 'X-Men' trilogy, and when the pair were on set together he felt like he was in an initiation ceremony where the legendary actor was handing over the ''baton''.

However, since there was few cast and crew around, unlike the usual bustle, it was like they were preparing to shoot intimate scenes.

Talking on XFM radio station, McAvoy said: ''Although I'd previously played Charles in one other movie, it still did feel like I was being initiated and that there was a baton being handed over. It was a very kind of ceremonial scene, in a very sort of ceremonial location. We were in a monastery, and the set was very quiet, and the director made sure that... It was much more like a sex scene.

''You know that when we do sex scenes we make sure there's nobody on set. It's just the boom operator, the camera man, and you don't have loads of people staring at you... usually we do!

''And it was a bit more like that. Clearing the set, making it very quiet, very reverent, that was kind of cool. It felt like I was being initiated into some kind of superhero sect!''

McAvoy joked about raunchy scenes with Stewart being a part of his ''wish list''.

show host Jon Holmes asked: ''You didn't worry that they were clearing the set, thinking, 'Is this a sex scene I hadn't red in the script, with me and Patrick'...?''

And McAvoy replied: ''A sex scene with Patrick Stewart would be exceptional. Tick that one off the wish list!''

Tune in to XFM radio station's X-Men FM from 6am-7pm.