Keith Urban can write a song at the drop of a pencil -- unless he's been assigned to write for a specific reason. The singer says when he was asked to pen a tune for the move 'Act of Valor,' he started having second thoughts. But after a representative from Relativity Films showed him the movie, he really wanted to write for it, in spite of the pressure it created.

"I'd never written for a particular thing before and I was really nervous about doing that," Keith tells The Boot. "Also it was right before my surgery last November, and I felt like I was on too much of a deadline to get it done. Then after I saw the film, I really wanted to do it but I couldn't think of an angle for the song."

Thankfully, Keith's wife, actress Nicole Kidman, urged him to try to write it. "She said to me, 'You should do this, you really should. I think you'll be able to do this if you commit to it.' She gently suggested that I do it and I'm glad she did."

Keith called in his songwriting buddy Monty Powell to work on it with him and then took another step that kept him on his toes.

"We were under such a time crunch to get it done that for the first time in my life I actually booked the studio before I had the song," Keith explains. "I thought to myself, 'Well if ever there was any pressure to get a song written it's now because the studio is booked and we have to have a song by next Wednesday.' Monty and I got together on Friday and did most of it, then got back together on Monday and finished it. Then I went into the studio on Wednesday and cut it."

The finished product is 'For You,' which will play during the movie's credits and appear on its soundtrack. So, Keith knows now that he can write a song for a movie, but why, so far, hasn't he acted in one? "Probably because I suck as an actor!" he says simply.

'Act of Valor' is based on the real-life incident of a group of Navy SEALs sent on a covert operation to rescue a CIA officer. The movie will be in theaters Feb. 24. The soundtrack, which includes the song by Keith as well as tracks from Hunter Hayes, Lady Antebellum and Montgomery Gentry, will be in stores Feb. 21.

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