HOLLYWOOD actor Liev Schreiber has confirmed his girlfriend Naomi Watts is pregnant with their child.

After denials, rumours, several slips of the tongue and Sydneysider Watts revealing a pronounced bump as she walked the Oscar red carpet this week, Schreiber ended the speculation last night during an interview on a US TV talkshow.

"I'm going to be a dad," Schreiber said during a guest spot on Late Night with Conan O'Brien.

"It's very exciting."

Schreiber, 39, and Naomi Watts, 38, fell in love while shooting the romantic drama, The Painted Veil, in China in 2005.

San Francisco-born Schreiber was unable to attend the Oscars with Watts as he was performing in the new Broadway play, Talk Radio, at Manhattan's Lonacre Theatre.

Schreiber joked how Watts had transformed into a party animal since becoming pregnant and was excited to take their unborn child to Hollywood's night of nights.

"It's a strange thing about women," Schreiber told O'Brien.

"You can take a complete wallflower, quiet girl, and you get them pregnant and suddenly they want to go out all the time and party.

"So, I gave her grief about going to the Oscars.

"But, she said no, it's a very auspicious thing that our embryo, I guess, was going to be on the Oscars."

Schreiber also joked how he has decided to leave all of the major decisions about the baby to Watts.

"I'm trying to stay out of it all," Schreiber, who starred opposite Denzel Washington in the 2004 re-make of The Manchurian Candidate, said.

"I'm trying not to make any decisions.

"Everything that I try to do in service of her or the coming baby is wrong. I really don't even go to my house much anymore."

O'Brien asked if "Liev" was a potential name for the baby.

"That's a distinctive name," O'Brien said.

"If you had a son is it possible you would name him Liev?"

Schreiber shot the idea down quickly.

"No. It's a terrible name," Schreiber said.

"It's probably the most mispronounced name in all of show business.

"It's bad enough I have gone through that, that a child would have to go through that as well.

"So, there won't be any Liev Jrs."

Schreiber also had the audience laughing as he told how during a recent four episode guest appearance on hit TV series CSI: Crime Scene Investigation the show's fans gave him a hard time.

The actor made the mistake of reading the CSI website's blog where fans called him creepy and ugly.

"It was really awful because I don't really think I am," Schreiber said.

"I don't listen to that.

"Look at my girlfriend.

"I've got a really hot girlfriend.

"You can't be creepy and ugly and have a hot girlfriend."

Watts' pregnancy became Hollywood's worst kept secret with the fashion house that dressed her for the Oscars, Escada, sending out a press release declaring she was pregnant.

Australia's Oscar winning Happy Feet director, George Miller, also revealed yesterday in an interview Watts was pregnant.