Oprah: Armstrong interview difficult

Oprah Winfrey said her interview with former cyclist Lance Armstrong was difficult. 

"He did not come clean in the manner that I expected," Winfrey said. "I thought that he was thoughtful, I thought that he was serious."

Armstrong was stripped of his seven Tour de France titles last year and was banned from the sport for life. For years, he had denied doping allegations. 

The interview will air Thursday on the OWN Network.