Paltrow not sure about Avengers 2

Gwyneth Paltrow has admitted she isn't sure if she'll sign up for the Avengers sequel - because she's getting older.

The 39-year-old has played Pepper Potts in the Iron Man movies and the character appeared in this year's Avengers Assemble, but Gwyneth has hinted that she might not reprise the role again in the planned follow-up.

She told E! News: "I don't know. I'm getting old for this s***, you know what I mean?"

Gwyneth was speaking at the Toronto International Film Festival premiere of her new movie Thanks For Sharing.

She said: "I just came off of Iron Man 3, which is as special effects-y and action-y as it gets. So to do something like [Thanks For Sharing] where it's really small, funny and exciting, is really great."

Last month it was confirmed a sequel to the Avengers movie - which starred Robert Downey Jr, Chris Evans, Mark Ruffalo and Scarlett Johansson - is in the pipeline and is expected to arrive in 2015.

Joss Whedon will be back to write and direct the as-yet-untitled sequel, and many of the main stars are expected to reprise their roles.

The third Iron Man film is due to be released in 2013.