Armstrong, who this year was slapped with a lifetime ban and stripped of his seven Tour de France titles for doping violations, has been named in a $1.6 million suit brought by The Sunday Times of London, the BBC reported Sunday.
In the suit, the newspaper is demanding Armstrong return a $485,000 settlement he obtained in 2006 after suing The Sunday Times for libel following the publication of stories alleging he had used banned performance-enhancing drugs.
The Sunday Times is also demanding he pay for its legal costs and interest, the BBC said.
The newspaper first reported allegations involving Armstrong and doping in 1999.
Armstrong has always denied he has taken banned substances, but has not contested the the U.S. Anti-Doping Agency's findings that he led a sophisticated program to use PEDs and evade their detection.