Paris Hilton Feels Sorry About Insulting Kim Kardashian

Paris Hilton has said sorry to best friend Kim Kardashian for insulting her voluptuous backside.

The hotel heiress had told a Las Vegas radio show Monday, "I would not want [Kim's butt] - it's gross! It reminds me of cottage cheese inside a big trash bag."

However, Hilton, 27, realized she had crossed the line after watching herself on the Internet when the clip was posted.

She tells In Touch magazine, "I was just joking around and I made a stupid joke. I felt really bad afterward, so I contacted Kim and apologized. It was a silly thing to say. Kim's hot!"