Singer Sheryl Crow faced questioning from federal authorities over sportsman Lance Armstrong's doping scandal last year, according to a new report.

The Grammy winner, who was once engaged to the former world cycling champion, was allegedly asked whether she had any knowledge about accusations that Armstrong was using illegal drugs to enhance his performance.

Armstrong won two of his now-invalidated Tour de France titles during his relationship with Crow, which lasted from 2003 to 2006.

Crow's interview with federal agents is believed to have taken place in late 2011, reports the New York Daily News.

Armstrong was last month stripped of his seven Tour de France victories amid an ongoing investigation based on allegations he used banned substances.