Chris Weitz, director of The Twilight Saga: New Moon, has admitted that the film's success has left co-stars Robert Pattinson and Taylor Lautner in a difficult situation.

Pattinson, who plays Edward Cullen, and Lautner, who stars as Jacob Black, have become huge box office draws as a result of the vampire franchise.

In an interview with People magazine, Weitz said he admired the way the pair handled their career both on and off screen.

"What I've realized is that they have a very tough job – not just playing the characters that they play, but living lives that are now very much under scrutiny all the time,” he said.

Weitz also revealed that social networking websites like Twitter had made it difficult to film New Moon in Vancouver.

"Everyone knows where every set is going to be,” he said.

“It goes with the Internet and all the information is out there all the time, and whenever one of them is spotted it's immediately Twittered."

But the director added that all of the cast handled the pressure well.

“They're smart kids – I can say that because I'm 40 – and they've got good heads on their shoulders. So they'll be all right."

New Moon, which is the second installment of The Twilight Saga, is released in cinemas worldwide on November 20.

The Boys of New Moon