Armie Hammer got aroused when he kissed Leonardo Dicaprio when they filmed 'J. Edgar'.

The 30-year-old actor portrayed Clyde Tolson in the 2011 biopic alongside the 42-year-old 'Titanic' star, who played the former FBI agent J. Edgar Hoover who was forced to hide his homosexuality, and when the duo locked lips in the intense kiss scene the 'The Man From U.N.C.L.E' has admitted he was left feeling rather frisky.

While appearing on 'Watch What Happens Live with Andy Cohen', Armie was questioned by the chat show host about whether he had a ''b***r or partial b***r'', to which the dark-haired hunk openly replied ''Yes''.

However the actor has revealed the actors did not use tongues when they filmed the steamy clip because they wanted to keep the movie ''respectful'', although he did admit the 'The Revenant' star has soft lips.

And Armie has admitted his wife, Elizabeth Chambers, was jealous of the intense snogging scene.

When asked if his spouse was filled with envy by the special moment he shared with Leonardo, he replied ''Yes''.

However, Armie can't decide whether the fight scene with his co-star or the kiss was his favourite part of the movie to film.

When asked: ''What was better at the time, Leo kissing you or Leo punching you?''

Armie replied: ''That's hard because I usually like to do both. So it's hard to pick.''

The production's filmmaker, Dustin Lance Black, took to social media after hearing Armie's revelation.

The creative mastermind tweeted: ''I remember this day on set quite well. I don't recall this particular detail though! Oh my. (sic)''

Armie is currently starring in a new film 'Call Me By Your Name', which is based on the 2007 novel of the same name, and will see the California-born star play a 24-year-old teacher who starts a sexual affair with a 17-year-old male pupil.