Jane Fonda has urged older women to "stay flexible" in order to have sex.

The 73-year-old actress knows not everyone is interested in making love as they get older but believes it is important to stay healthy and active.

Speaking at the 30th anniversary party of Shape magazine, where she was honoured with a Lifetime Achievement Award, Jane - who appeared on the cover of the publication in September 1987 -said: "You have to want sex, and many people don't. That's just fine.

"You don't have to want sex when you're older, but if you want sex, you have to stay flexible, and you have to stay healthy, and you have to feel OK about yourself."

Guests at the party included reality TV stars Kelly Bensimon, Ashley Herbert and Dana Wilkey and past former cover models, while singer JoJo entertained the crowd at the IAC Building in New York.

Jane - who has been married three times - has previously said she enjoys sex more now she is older and insisted she is happier than ever thanks to her active lifestyle and understanding of life.

She has said: "I'm 71 and physically don't feel so good since I'm in pain. But I'm happier, the sex is better and I understand life better. I don't want to be young again.

"How do I still look good? I owe 30 per cent to my genes, 30 per cent good sex, 30 per cent are because of sports and healthy lifestyle with proper nutrition and for the remaining ten per cent I've to thank my plastic surgeon."