Kirstie Alley is determined to be "ripped" and look like First Lady Michelle Obama by the time she launches her new weight loss brand in November.

The star has gained back all the weight she lost while she was a spokeswoman for diet company Jenny Craig in 2007 - and then some. And now she's fighting to get thin again.

Appearing on pal Oprah Winfrey's show - where she once showed off a post-diet bikini body - on Thursday, Alley discussed her plans to shape up, insisting she had already lost 20 pounds in five weeks and hopes to look like the U.S. President's wife by November.

She says, "By November I have to look ripped."

And she's aiming for Obama's body: "I could have those arms; I don't know about the legs. My whole issue is my butt and my legs, so I have to get pretty thin to have a really good butt and legs."

(This news article provided by World Entertainment News Network)