The Sunday Times announced in an article in its latest edition that it has issued legal papers against Armstrong.
"It is clear that the proceedings were baseless and fraudulent," the paper said in a letter to Armstrong's lawyers. "Your representations that you had never taken performance enhancing drugs were deliberately false."
The paper, which is owned by Rupert Murdoch's News Corp., said its total claim against Armstrong is "likely to exceed" 1 million pounds ($1.6 million).
"The Sunday Times is now demanding a return of the settlement payment plus interest, as well as its costs in defending the case," the paper said.
World champion Kelsey Serwa, of Canada, won at San Candido, Italy, in her first ski cross race since returning from an injury, ending Swiss rival Fanny Smith's run of three straight victories to open the season. Serwa won the opening two World Cup races at San Candido last season before sustaining a knee injury.
She looks back at her best, having dominated the quarterfinal and semifinal, then rallying from last to first in a wild final Sunday, which saw Swiss standout Katrin Mueller spin out and French veteran Ophelie David disqualified.
Canadian teammate Georgia Simmerling finished second, and Mueller ended up third.
Smith still leads the standings.
In the men's final, Switzerland's Alex Fiva got his first victory this season, finishing ahead of Germany's Daniel Bohnacker and Sweden's Victor Oehling Norberg.