LONDON: Sienna Miller and Rachel Nichols struck up such a close friendship on the set of G.I. Joe, they spent Valentine's Day together.

The Alfie star bonded with Nichols between takes and the pair turned to each other for comfort during their time spent making the action movie.

Single Miller and Star Trek actress Nichols, who split from producer husband Scott Stuber earlier this year, even spent the most romantic day of the year in each other's company.

Miller says, "We needed each other - it (film set) was a very testosterone-fuelled environment. We actually spent Valentine's Day together, in my bed!"

Nichols adds, "We all got on so well making the film - we spent all of our time together."