Greta Gerwig admits Russell Brand made her "blush" all the time on the set of 'Arthur'.

The actress - who plays Naomi, Russell's titular character's love interest, in the movie - admits she was often the butt of the British actor's jokes, and she admits nothing was out of bounds for risque Russell.

Greta told BANG Showbiz: "He made fun of me all the time! Of everything - things I came to the set wearing, things I was doing, but he is still charming when he's making fun of you.

"I think I just blushed a lot and got awkward, which he also enjoyed. But that's his natural state with women, men, everyone - to flirt, he's just so magnetic, he can't help it."

Despite his relentless gags, 'Greenburg' actress Greta insists Russell was "really hard working" and great to work with.

She added: "Russell never really delivers the same line twice, and I come from a background of improvisation, so I quite enjoyed that and I like keeping it fresh, it's good, it makes every take different."