Benicio del Toro and Kimberly Stewart expecting a baby together

It is one of the more surprising pregnancy announcements.

This week, Benicio Del Toro revealed that he is expecting his first baby – with Rod Stewart's daughter Kimberly.

"Kimberly is pregnant. Benicio is the father and is very supportive," a spokesman for the Oscar winning actor told Life & Style magazine.

"Although they are not a couple, they are looking forward to the arrival of the baby."

News that 31-year-old Kimberly is expecting will come as a surprise to many – she and Benicio, 44, managed to keep news of their liaison out of the spotlight, and have never been photographed together.

One man likely to be delighted by the announcement is her father Rod, who himself recently welcomed his eighth child - and his second son with Penny Lancaster.

It is thought that he will become a grandfather for the first time when Kimberly – his daughter with first wife Alana Hamilton - delivers her baby.

Model Kimberly has been linked in the past to British actors Jude Law and Rhys Ifans. Benicio, meanwhile, has reportedly enjoyed romances with stars including Scarlett Johansson and Minnie Driver.