'Breaking Dawn Part 1' still. Entertainment One.

While he hit out at reports that the couple - who have been in a long-term relationship since meeting each other on the set of the 'Twilight Saga' films – are already engaged, Robert says it is a distinct possibility in the future because he has never felt this way about anyone before.

He told BlackBook magazine: “There was a magazine, with these pictures, saying I was getting married. No one ever knows what is true or what isn’t. Even my own mum called to ask me if it was true. It’s not. At least, not yet. But it is true that Kristen has always done something to me that others haven’t."

Robert also revealed being famous has its disadvantages, such as having to pay full price for things because he can no longer claim poverty.

He explained: “I learned to drive by people crashing into me. The first time anyone said anything about my being famous was when I tried to buy a car a few years ago. It was an ’89 BMW convertible for $1,000 I found on Craigslist.

"I went out to the hills to take it on a test drive and, of course, almost crashed. A few days later I went back to pick it up. I had said I was an actor and the guy had looked me up. When I went back, he said, ’Dude, do you know you’re number two on IMDB? I thought, ‘S**t, now I can’t ask for the 200 bucks off.'"