Local news crews stake out outside of Lance Armstrong's home in Austin, Texas, January 14, 2013. Cyclist Lance Armstrong confessed to using performance-enhancing drugs in an interview on Monday with Oprah Winfrey, USA Today reported.  [Photo/Agencies]

"He had a private conversation with the staff, who have done the important work of the foundation for many years," said Livestrong Foundation spokeswoman Katherine McLane.

"It was a very sincere and heartfelt expression of regret over any stress that they've suffered over the course of the last few years as a result of the media attention," she said.

Shortly after, Armstrong joined his legal team to meet with Winfrey for an interview described as "no-holds-barred".

The interview was supposed to take place at Armstrong's home in Texas but was switched to a hotel in downtown Austin after news crews camped outside his house before dawn.

But an October report from the US anti-doping body USADA cited Armstrong's involvement in what it characterized as the "most sophisticated, professionalized and successful doping program that sport has ever seen," involving anabolic steroids, human growth hormone, blood transfusions and other doping.

Less than two weeks later, Armstrong's seven Tour de France victories were nullified and he was banned from cycling for life after the International Cycling Union ratified the USADA's sanctions against him.

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