The 35-year-old, who married third husband, singer Marc Anthony in June last year, was scheduled to fly to London to promote the film, Shall We Dance?, with co-star Richard Gere.

But she called off the trip at the last minute, saying she was "not well".

Lopez issued a statement saying: "I very much wanted to be in London today but unfortunately I'm not well.

"At the advice of my doctors I'm unable to travel. Being sick has also caused me to cancel my European album tour.

"Please accept my sincerest apologies as I have to remain in Los Angeles."

Fans flocked to the premiere despite Lopez's absence.

The film's director, Peter Chelsom, was philosophical over the no-show.

"I'm disappointed. It's a shame. I know it's true that she's not well because she has also cancelled her promotional tour. I've heard she has swollen glands," he said.