All her life Yoko Ono has suffered sexism and racism. Now, as she celebrates her 70th birthday, she is determined not to suffer from ageism.

"I suffered all my life from sexism, like most women do, and racism, and I thought am I going to add ageism to this?" says the widow of John Lennon in her only birthday interview.

"When I was turning 60 it was nothing, but when I was 69 I was thinking 'oh no am I going to have to fight ageism as well'.

"So I suppose I did feel a little bit bad about that, then I realised the good side, the fact that I should be thankful."

Yoko, who is speaking to me from New York, says she will be marking her seven decades with a grand party arranged by her son Sean, 27, in her favourite New York restaurant.

And last night Yoko, who is showing no signs of slowing down, performed her new dance-style single at a Manhattan club. The track Walking On Thin Ice is a collaboration with the Pet Shop Boys and American DJ Danny Tenaglia.

She says: "I'm very excited that people love the record. I've been asked to come over to Britain and play in some electro clubs and I think I will do that," she says.

"This feels like a new beginning for me with the dance community adopting me and my music. It's a very exciting time for me."

font color="#FFFFFF">It is difficult to believe that it was more than 20 years ago when John was shot dead outside the couple's home.

Yoko still lives at the Dakota Building she shared with John - a stone's throw from the Strawberry Fields peace memorial. And every day it is a reminder of her youth and her time with the former Beatle.

They married in 1969 and invited the world's press to their honeymoon spent in bed at the Amsterdam Hilton.

"I look at old photographs of John and I and I think that just seems like yesterday," she says. "But it seems to me that age is what you make of it. They say that time is a man-made concept so if you don't make it then it's not there!"

Yoko was 47 when her husband was shot dead in 1981. But in the years they were together, one birthday present stands out.

"The favourite birthday present I ever received from John was when I woke up one birthday in the morning and there was a gardenia next to me on the floor," she recalls.

"It is a flower that I like because its scent is so sweet. It is beautiful. There was this one gardenia on the floor at the side of my bed. Then I saw another and another, then another. I went down the stairs and they were full of the flowers, too. Then, when I got downstairs, there was an ocean of gardenias; they were everywhere. They were so beautiful.