Weisz stars in the John Le Carre adaptation The Constant Gardener

The Golden Globe-nominated star said she and her fiance, film director Darren Aronofsky, have had to postpone their wedding due to the pregnancy.

Weisz, 34, told Jay Leno's Tonight Show it was a "slightly modern" situation that she was still trying to work out.

The actress, whose previous films include the Mummy, is up for a best supporting actress award for her role in The Constant Gardener.