KRISTEN STEWART - STARS OF TWILIGHT EXPECT TOUGHER TIME WITH SEQUEL NEW MOON

STARS OF TWILIGHT EXPECT TOUGHER TIME WITH SEQUEL NEW MOON

The record-breaking success of vampire romance Twilight has put pressure on its sequel New Moon, its leading actors have admitted.

The literary adaptation made $70.6 million (£47.4 million) in its opening weekend in the US to achieve the best-ever box office debut for a female director.

Its surprise popularity resulted in a sequel being quickly given the go-ahead, for which stars Robert Pattinson and Kristen Stewart will both return.

"We had nothing to lose in the first one," said British actor Pattinson, who was previously best known as Cedric Diggory in the Harry Potter films.

"It's harder to build up the hype, especially in America. I think it will be harder," he told a recent London press conference.

Stewart, who plays awkward teen Bella Swan in the film, added she expected the critics to be "a little tougher" on the sequel when it opens in late 2009 or early 2010.

"I knew how important it was to a small group of people. I didn't realise how widespread they (Stephenie Meyer's books) were," she said.

"I think the film made it more well-known. When we were making the movie we thought it was kind of a cult film."

About A Boy helmer Chris Weitz is to direct New Moon, after it was revealed that Twilight director Catherine Hardwicke would not be returning for the follow-up.

She withdrew from the project earlier this month, reportedly over concerns that the studio was overly committed to releasing the film in a year's time.

Twilight opens in the UK on Friday December 19th.