London, June 23 (ANI): Billie Piper has posed inside a champagne glass to promote her saucy TV series 'Secret Diary Of A Call Girl.'

The pic has been displayed all over billboards and buses in the US for the Stateside launch of the show, reports the Sun.

And the promotion has paid off, for the show is now the No 1 programme on the Showtime channel.

The series, which stars Piper as high-class vice girl Belle de Jour, caused a stir in Britain after the 25-year-old appeared in steamy scenes - including brandishing a riding crop while with a client and enjoying a lesbian kiss.

Billie, expecting her first baby with hubby Laurence Fox, is presently filming the second series of the ITV2 hit. (ANI)