Ashton Kutcher has revealed that he was forced to buy a multi-million dollar mansion so that Justin Bieber wouldn't purchase it from under him.

The 34-year-old Two and a Half Men star moved into a rental property earlier this year after the breakdown of his marriage to Demi Moore.

Ashton told Jimmy Kimmel on his late night chat show that the 18-year-old pop star, who also appeared on the programme, was poised to buy the luxury property if he didn't take drastic action after Justin went to view the Hollywood Hills pad.

"I had to buy the house because I thought he was going to buy it out from under me," he laughed. "I was like, I don't want to lose this house.' He forced me to buy a house. He's trying to steal my swagger."

Ashton said he found the property on an internet travelling site and had initially agreed to rent it for just a short time.

"I knew I had to come back and do Two and a Half Men in January so I found this amazing house in LA that was on Air B&B," he recalled. "And I booked this house to stay in for three months. I was away, I booked the house, it was all done."

But before Ashton could even properly unpack, he was told that Justin was interested in snapping up the home.

"All of a sudden my assistant tells me there's somebody coming to look at the house to maybe buy it," he laughed pointing at Justin. "I get a text from this guy and he's in my house, checking it out, trying to buy my house."

"He's like, Yo, I'm in your house right now. I'm checking it out.' I'm like What? Are you trying to take my house from under me?'"

Justin then chimed in that Ashton advised him not to pay more than $9.5 million and was "like my big brother, giving me real estate advice."

Ashton and Justin are working together on the new series of Punk'd which the pint sized pop star is guest hosting.