Kris Jenner: 'Affair was the biggest regret of my life'

Kris Jenner has described cheating on ex-husband Robert Kardashian as "the biggest regret of [her] life".

The reality star's 12-year marriage to her teenage sweetheart broke down after she embarked upon an affair with a producer named Ryan.

Speaking of her relationship with Kardashian, Jenner told The Tonight Show With Jay Leno: "He was the only guy that I had dated. When you're very young you do a lot of stupid things. and it's probably the biggest regret of my life that I ended up having an affair.

"[I was] probably just really naive and stupid and restless and didn't realise that marriage has its ups and downs. Someone once told me that it's like a roller-coaster, just ride it out, but I wasn't really old enough to hear those words."

The 56-year-old has discussed the affair further in her memoir Kris Jenner...And All Things Kardashian, claiming that she was suffering from a premature mid-life crisis and revealing that she and Ryan "had wild sex everywhere, all the time" before being caught.

Robert Kardashian died of esophageal cancer on September 30, 2003.

Jenner recently claimed that she is unsure whether her daughter Kim Kardashian will reunite with estranged husband Kris Humphries. The couple divorced last week after just 72 days of marriage.

Watch Kris Jenner on The Tonight Show below: