Image caption Armstrong ended his fight against doping charges last August but has maintained his innocence

Lance Armstrong has apologised to the staff at his Livestrong Foundation, amid reports that the US cyclist may admit doping in a TV interview.

Armstrong made the personal apology during private conversations in Austin, Texas, a foundation spokeswoman said.

His interview with Oprah Winfrey is due to be broadcast on Thursday.

Armstrong, 41, was stripped of his seven Tour de France titles by the sport's governing body last year. He has maintained his innocence.

"He had a private conversation with the staff, who have done the important work of the foundation for many years," Livestrong Foundation spokeswoman Katherine McLane was quoted as saying by Reuters.

I'm calm, I'm at ease and ready to speak candidly Lance Armstrong

"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 added.

Armstrong, who also received a lifetime ban from governing body the International Cycling Union (UCI) and the US Anti-Doping Agency (Usada), was reportedly close to tears.

It was not quite a confession of sustained cheating, but that is what many in the cycling world and across America are expecting to hear when they tune in to the cyclist's interview on 17 January, the BBC's Paul Adams in Washington reports.

The recording of the TV interview - his first since being stripped of his wins - took place on Monday.

After recording the interview, Winfrey tweeted: "Just wrapped with @lancearmstrong. More than 2 1/2 hours . He came READY!"

A spokeswoman for the Oprah show said last week that Armstrong was not being paid to appear and that Winfrey was free to ask him any question she wanted.

The choice of America's favourite agony aunt to conduct the interview suggests that Armstrong is prepared to make some kind of confession, our correspondent says.

At the weekend, Armstrong told the Associated Press: "I'm calm, I'm at ease and ready to speak candidly." He declined to go into further details.

'Confession obstacles'

Armstrong ended his fight against doping charges in August 2012.

In October, Usada released a 1,000-page report saying he had been at the heart of "the most sophisticated, professionalised and successful doping programme" ever seen in sport.

Armstrong also later resigned as chairman of the Livestrong Foundation, the cancer charity he created.

His lawyer, Tim Herman, has described the Usada report as a "one-sided hatchet job" and the cyclist himself has accused the agency of offering "corrupt inducements" to other riders to speak out against him.

It is believed he is considering an admission because he wants to resume his athletic career, and has shown an interest in competing in triathlons.

The BBC understands Armstrong has held recent discussions with other cyclists who have themselves confessed to doping.

But there are a number of obstacles to a full confession.

The New York Times has reported Armstrong's supporters are concerned he could face perjury charges if he confesses to using performance-enhancing drugs, because he made sworn testimony in a 2005 court case that he had never done so.

In addition, the cyclist faces a number of legal cases.