Bradley Cooper was once dumped by a girl while breathing through an oxygen tank.

The 'Hangover' star - who used to be married to the actress Jennifer Esposito - was told by a former lover that their relationship was over while he was in Peru and battling altitude sickness.

He told UK station Radio 1: "The worst time I was dumped was overseas on a bad line of a telephone. I was in Peru with an oxygen tank because I hadn't acclimatised properly. It was the worst time. She's a sweetheart though."

The 36-year-old actor was previously in a relationship with 'Bridget Jones' Diary' star Renee Zellweger and has in the past been romantically linked to former 'Friends' actress Jennifer Aniston.

Bradley recently starred alongside Academy Award-winner Robert De Niro, who he has described as "the greatest".

He added: "Robert De Niro is the greatest. If you look at the roles he's done, nobody really compares to him. Daniel Day-Lewis is on his way, but if you look at the variety of roles Robert's played it's incredible, it's just nuts."