Zoe Saldana has confirmed she is expecting twins.

The 'Guardians of the Galaxy' actress - who confirmed her pregnancy for the first time last month - has admitted she and husband Marco Perego will be welcoming two babies into the world in the coming months after being quizzed on her plans for Halloween.

Asked if she will be dressing up for the spooky celebration, which takes place on October 31, she rubbed her growing baby bump and told E! News: ''I might. I might need three costumes. I might have to make some adjustments, but it would be nice.''

Zoe's admission came a few weeks after her friend and 'Crossroads' co-star Britney Spears accidentally let slip she is having twins.

Asked whether she would like to film a sequel to her 2002 film with Zoe, Britney said: ''Who knows? That's a very good idea. But she's pregnant with twins right now. So I'm sure she's got a huge future ahead of her.''

Asked if she had any advice for the 36-year-old star, the 'Perfume' hitmaker, who has sons Preston, nine, and Jayden James, eight, with ex-husband Kevin Federline, joked: ''You're not ready. You don't know what you're in for.''

Following a lot of speculation, Zoe acknowledged her pregnancy for the first time last month in an ALS Ice Bucket Challenge video in which she nominated her husband to take her place and complete the task by having freezing water poured over his head to raise awareness for the nerve cell disease.

Turning to the side and rubbing her growing baby bump, the 'Avatar' star, who was nominated by director James Gunn, said in a video of the event: ''I am accepting James Gunn's challenge to take on the ice bucket challenge.

''Obviously, I can't do it myself so I nominate my husband to take on the challenge and get rinsed with a nice bucket of ice water.''