Presenter of ITV programme GMTV Kate Garraway is set to sue newspapers for libel over comments she alleges were "hurtful" and "untrue".
The 39-year-old, who is married to Derek Draper, was angered by articles that appeared in the Sunday Mirror and Daily Mirror that, her lawyers say, suggested she was having an affair with professional dancer and Garraway's partner on Strictly Come Dancing Anton Du Beke.
Commenting on the rumours, she said: "Contrary to these insinuations, Derek and I are as faithful, happy and in love today as we have ever been.
"The plain truth is that Anton and I became friends during Strictly Come Dancing."
Trinity Media, which publishes the Sunday Mirror and Daily Mirror - as well as three other national titles and over 150 regional newspapers - had no immediate comment.
Libel proceedings have now begun in London's high court.