Arnold Schwarzenegger has admitted that his rivalry with Sylvester Stallone got “out of control” when they started to “derail each other”.Appearing on a new episode of The Graham Norton Show, which is due to air this evening (October 27) on BBC1 at 10:40pm, Schwarzenegger admitted that they would compete against each other in their various action films and would attack each other in the press.The pair later became friends after collaborating on projects together, including film franchise The Expendables and 2013’s Escape Plan. Schwarzenegger went on to say they are now “inseparable”.Schwarzenegger said: “We were movie rivals, but we took the competitiveness to the extreme – we each had to have the best body, we had to kill more people in our films, and we had to have the biggest guns.“It got out of control, and we tried to derail each other.