Christian Bale thinks Donald Trump thought he was Bruce Wayne.

The 'Dark Knight Rises' star - who also played the Caped Crusader in 'Batman Begins' and 'The Dark Knight' - shot scenes for the sequel at Trump Tower back in 2011, and he has revealed his ''entertaining'' meeting with the current US president while quipping he thinks he mistook him for the superhero's billionaire alter ego.

Speaking to Variety, he joked: ''I met him, one time. We were filming on 'Batman' in Trump Tower and he said, come on up to the office.

''I think he thought I was Bruce Wayne, because I was dressed as Bruce Wayne. So he talked to me like I was Bruce Wayne and I just went along with it, really. It was quite entertaining. I had no idea at the time that he would think about running for president.''

Bale is taking on the role of former vice president Dick Cheney in new political comedy drama 'Vice', and he also opened up about his weight gain for the role.

The 44-year-old actor has drastically altered his appearance for movies in the past, including losing 63 lbs for 2004's 'The Machinist' and then gaining 100 lbs back within six months for his first big screen appearance as Batman.

However, this time he decided to see a ''nutritionist'' because he is becoming aware of his own ''mortality''.

He explained: ''This is the first time I actually did go to a nutritionist cause I'm starting to feel my mortality.

''I did decide, 'You know what, I might die, so maybe I should go to see someone who actually knows what they're talking about instead of just winging it,' which is what I've always done.''