Justin Timberlake discusses sex scenes with ex Cameron Diaz

The pair may have dated off-screen for nearly four years, but the Social Network star didn't find filming intimate scenes with Diaz, 38, strange.

Speaking to Access Hollywood at the film's junket in Los Angeles yesterday, the 30-year-old said: 'I didn't look at it like that.

'We obviously know each other, but I looked at it as a really funny, funny scene that I have never seen done before.'

One thing Justin did find difficult was filming close-ups for the steamy scene by himself.

The SexyBack hitmaker added: 'What I actually remember was, you know, they got to my close-up for that scene, so I was just kind of by myself - which is hard to imitate in real life.

'Jake [Kasdan], the director, kept yelling out, 'OK, more contorted! Uglier face! Flare your nostrils! Curl your lip up... more!' And I'm trying not to laugh.

'I saw it [played] back one time and I'm really emotionally damaged.'