Speaking on Los Angeles radio station KIIS-FM on Friday, Madonna said she had no idea M.I.A. made the gesture after joining the pop superstar on stage during the halftime show, which was watched on television by more than 114 million Americans.

"I didn't know about it until I left. I was really surprised. I didn't know anything about it," she said, adding that she was not happy.

"I understand it's punk rock and everything, but to me there was such a feeling of love and good energy, and positivity. It seemed negative. It's one of the those things, it's such a teenager, irrelevant thing to do ... what was the point? It was just out of place," she added.

The NFL and broadcaster NBC both apologized to U.S. viewers, saying the transmission delay system in place to prevent such incidents had failed to work properly.

The watchdog group Parents Television Council protested, blaming both the NFL and NBC for hiring performers "who have based their careers on shock, profanity and titillation".

The Federal Communications Commission, which regulates the use of profanity and nudity on network television, has declined say whether any official complaints have been filed.

(Reporting By Jill Serjeant; Editing by Bob Tourtellotte)

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