Veteran actor Al Pacino has sparked speculation he is planning to propose to actress Lucila Sola after conceding it is "very possible" the couple will wed.

The 74-year-old star, who has never married despite a string of high-profile relationships, has been dating Sola for five years and reveals he is open to tying the knot.

Pacino tells Total Film magazine, "Of course (marriage) is possible. I have no idea but I never say never. It's very possible this could happen."

The Oscar-winning actor has a 25-year-old daughter, Julie, with acting coach Jan Tarrant, and 14-year-old twins, son Anton James and daughter Olivia Rose, with actress Beverly D'Angelo.