Star couple reveal Top Gear rivalry

The two A-listers, who are promoting their movie Knight And Day, competed to complete the fastest lap, and the results will be shown on Sunday.

Diaz, who glittered on the red carpet in a silver sequinned Stella McCartney minidress, added: "We did timed laps. It's very exciting – we know the score and we want to tell everybody, but we can't because we want them to watch the show."

It is the duo's first film together since 2001's Vanilla Sky.

Cruise heaped praise on his co-star, saying: "Cameron is such a great actress to work with."

Diaz responded: "Tom is just amazing and so much fun. We had a laugh every day, and did the best work we could."