Kate and Sam go public

Kate Winslet and Sam Mendes have appeared in public together for the first time - just hours after the publication of an interview in which she spoke about her separation from her husband and shared her thoughts on divorce.

The 26-year-old British actress attended the New York premiere of her new film, Iris, based on the life of the novelist Iris Murdoch last night with Mr Mendes. They stood hand-in-hand and at one point the Titanic star leant over to give him a kiss on the cheek.

"They were clearly thrilled," an onlooker said. "He started by holding her around the waist, and then she held his hand and reached over to kiss his cheek.

"I don't think anyone really thought they would arrive together, but they clearly wanted to let the world know how happy they are."

In the interview published in the US yesterday, Ms Winslet said: "Life is life, and divorce happens to lots of people. When your first priority is the happiness of your child, that is the first thing you have to think about and then act accordingly. That's simply what we did."

"We all want to be with a life partner and hope that it's everlasting. Sometimes it doesn't happen."

However Ms Winslet headed off any further questions about her three-year marriage to assistant film director Jim Threapleton, 27. "The details of the divorce are completely confidential," she added."

News of Ms Winslet's new relationship emerged after Mr Mendes, the award-winning director of American Beauty, stayed at a Texas hotel with Ms Winslet and her 14-month-old daughter Mia.

Mr Mendes, 35, later admitted: "Yes, we are having a relationship. It's early days and we're very happy." He denied playing a part in the breakdown of her marriage. ""She'd already split from Jim when we met," he said. "Some time in September it went from being friends to something deeper."

During her marriage, Ms Winslet was more than forthcoming about her personal life. But now she says: "I'm getting more private as I get older, especially in terms of relationships. I basically won't talk about them."

Still, she's happy to talk about her daughter. In the interview she said: "Being a single mother is not remotely daunting. There's an instinctive strength that just kicks in. I didn't get a nanny until she was nine months old. It's absolutely exhausting, but I wanted to experience all those things."

Ms Winslet also described how hard it was to leave Mia behind when she works. "At times it's slightly heartbreaking. She knows when I'm going to work, and her lip starts to quiver when she waves bye-bye."

She added: "I feel very much like a woman, although I have my girly moments. Having had a child, I feel stronger and more in tune with who I am. It changes your life, but it hasn't changed me as a person. I still have enormous determination and strength. I feel as though I can accomplish anything."

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