Actor Mel Gibson has confirmed his Russian girlfriend is expecting their baby. The star, who is going through a divorce with his wife Robyn after 28 years of marriage, confirmed the news during an appearance on The Tonight Show With Jay Leno. When the host asked him about rumours that suggested musician Oksana Grigorieva was pregnant, Gibson said "this is true" but gave away few details. He joked that they were having "a human being, I think" when he was asked about the baby's gender. Mrs Gibson filed for divorce last month, citing irreconcilable differences with the star. Gibson told Leno that he'd done "a pretty good hatchet job" on his marriage and that he and his wife split up three years ago, shortly after he was arrested in Malibu for drunken driving. He also revealed that he met Grigorieva, 39, in 2008 after the singer/pianist had been signed to his Icon Records label. They appeared in public together a month ago at a Los Angeles industry screening of X-Men Wolverine: Origins.