Retired Tennis champion Billie Jean King will not attend Friday’s opening ceremony of the Sochi Winter Olympics in Russia because her mother is ill.

Last December, US President Barack Obama named King as part of America’s delegation to the Winter Olympics in Russia.

The gay former tennis player has been outspoken in her opposition to Russia’s anti-gay laws.

She had planned to attend ice hockey and figure skating events and meet US athletes during her three-day visit to the Games which begin on Friday.

King told The Associated Press on Wednesday that because of her mother’s “failing health, I will not be able to join the US Presidential delegation at this week’s opening ceremonies of the Sochi Olympics.”

Betty Moffitt, her 91-year-old mother, lives in Arizona and has been ill for some time.

“It is important for me to be with my mother and my brother at this difficult time. I want to thank President Obama for including me in this historic mission and I look forward to supporting our athletes as they compete in Sochi.”

The White House announced that former US hockey player Caitlin Cahow, originally scheduled for the closing ceremony, will take King’s place.

Former figure skater Brian Boitano, the third gay member of America’s delegation, went public about his sexuality in December, following the decision of President Obama decision to include him in the delegation.  

In January, Billie Jean King suggested that athletes should think twice about protesting for LGBT rights at the Games – because it could mean they face disciplinary action by the IOC.