London, Feb 5 (ANI): Jessica Alba was left embarrassed while filming a kiss scene with Ashton Kutcher for upcoming movie 'Valentine's Day' - because her chewing gum almost fell out of her mouth during the act.

The actress has admitted that locking lips with her Hollywood pal was 'awkward' to shoot - but shooting the scene got even more uncomfortable when a glob of her gum got stuck on her lip as Kutcher leaned in for a smooch.

"Whenever I'm nervous I have gum on the roof of my mouth - so I had it (during the scene) and my mouth got dry because I was nervous because I knew I was going to kiss Ashton. It got powdery and it got on my lip during my close-up," the Daily Star quoted her as saying.

Alba said that her co-star Kutcher spotted the sticky situation and refused to let her blooper go unnoticed.

"He (Kutcher) called me out in front of the whole crew. It was really embarrassing," he said. (ANI)