A Hong Kong tycoon has withdrawn his $130 million "marriage bounty" to find his lesbian daughter a male suitor after she defended her sexuality in a heartfelt open letter, but emphatically refused to accept her partner into the family.

Gigi Chao asked her father, flamboyant property developer Cecil Chao, in an open letter Wednesday to treat her partner of nine years as a "normal, dignified human being".

Her plea came after Chao, who refuses to recognise her as a lesbian, last week doubled the "marriage bounty" on his daughter to HK$1 billion ($130 million).

The initial offer of HK$500 million two years ago attracted 20,000 candidates after the outlandish declaration made international headlines.

"If this is what she wants to be for the time being, it?s all over," the elder Chao, wearing a bright orange textured coat and dark-tinted sunglasses, told CNN in an interview Thursday.

"I?m not trying to use money to buy her happiness, she has to choose her own happiness, but I can use my money to let her have a choice," Chao said, while implicity suggesting that his daughter's sexual preference may change over time.

"She is only 33. Life changes. I mean I changed a lot when I was 33 to now."

But the 77-year-old refused to accept her partner Sean Eav into his family.

"I don?t have to accept her partner, it?s for her to accept her partner," he said, emphatically replying "no" when asked if Eav would be accepted into the family.

In her letter, which starts "Dear Daddy", Gigi Chao -- who reportedly married Eav in France in 2012 -- said she knows it is difficult for her father to understand how she could feel attracted to a woman.

"I suppose I can?t really explain it either. It just happens, peacefully and gently," she wrote in a letter circulated to Hong Kong media.

She said she forgave her father because he was acting in her best interests.

"My regret is that you have no idea how happy I am with my life, and there are aspects of my life that you don?t share," she said.

British movie maker Sacha Baron Cohen is reportedly working on a film based on the story.

Chao, who owns publicly listed property developer Cheuk Nang, is a fixture of Hong Kong high society and regularly appears at public events with his latest young girlfriend. He once reportedly claimed to have slept with 10,000 women.