The 'Candy' singer is happily married to actress Ayda Field - who recently gave birth to their first child, daughter Theodora - but admits he would find it hard to turn down a bedroom liaison with the sexy 'Ted' star.
When asked if he would like to entertain Mila, Robbie - referring to a budget British hotel chain - quipped: ''I'm married and I respect and love my wife too much.
''But, that being said, if Mila could meet me at the nearest hotel, the Travelodge. I don't know if she's been to Keele Services before, but at Keele Services there is a Travelodge. It's only £27.99 for the afternoon, Mila, I'll see you there.''
He said: ''Not again. You know how much trouble I got in last time. He nearly found out, you know. This is embarrassing for both of us, I'm married now.''
The 38-year-old pop star also spoke about his love for his baby daughter, and admitted he's happy to change Theodora's dirty nappies and even finds the unpleasant job a ''cosmic'' experience.
He said: ''It's so many things, words don't do it justice.
''The closest thing to it would be cosmic, spiritual, messy. Very chicken tikka.''