The pair are currently travelling the world to promote new film Total Recall, and have been the subject of several 'fashion war' articles.
> Total Recall premiere: Kate Beckinsale, Jessica Biel walk red carpet
"I think the media always loves to pitch two women against each other," Biel told the Magic 105.4 Breakfast show.
"They would not do it with two guys you know, 'What suit is he wearing or what suit is he wearing, nice black shoes'. It's not competition between us. You know we do actually call each other occasionally."
Mocking such press reports, she added: "'Grr, she beat me, I'm gonna get her next time' - unfortunately It's just not true. Yes, we're having such a good time. Travelling around like this is even more intimate than shooting."
Biel also described co-star Colin Farrell as "respectful" and a "good" guy, explaining that he has a "sparkle" and "curiosity of life".
Total Recall, which opens in UK cinemas on August 29, is a remake of Arnold Schwarzenegger's 1990 sci-fi classic.
Farrell plays a factory worker who begins to suspect that he is a spy with fake implanted memories.
Watch a clip of Total Recall below: