Being an international superstar and a single mother of four is not an easy job!

Madonna admits in a new interview with Rock Center's Harry Smith that she needs to be a tougher mother.

The singer's oldest daughter, Lourdes Leon, 15, was recently photographed smoking a cigarette.

PHOTOS: How Madonna's face has changed

"[I] wasn't very happy," Madonna, 53, said of seeing the photos. "But honestly, I don't think I'm as tough as I should be [on my kids]. I think I need to be maybe tougher. It's hard -- every day is a negotiation." (Madonna is also mom to Rocco, her 11 year old son with ex-husband Guy Ritchie, plus David, 6, and Mercy, 5, whom she adopted; Lourdes' dad is Madonna's former beau Carlos Leon.)

"But cigarette smoking I'm not very fond of for anyone," she added. "I don't approve of anyone smoking cigarettes -- most of all my daughter." 

Yet, as Smith points out in the interview, the pop queen herself smokes in her racy new "Girl Gone Wild" video.

"I don't smoke," she fired back with a big smirk on her face. "That's just an accessory, Harry. There's a difference. [Lourdes] smoked that cigarette before I did that video!"

PHOTOS: Madonna wannabes

Madonna's full interview airs Wednesday night on Rock Center with Brian Williams at 9 p.m. ET.

Tell Us: Do you think Madonna smoking in her video is hypocritical?

Get more Us! Follow us on Twitter, Friend us on Facebook, Subscribe to Us Weekly