Keith Urban gushes about Nicole Kidman on stage

London: Singer Keith Urban paid a heart-warming tribute to his wife, Nicole Kidman, while performing in Australia.

The 46-year-old country singer, who previously credited his wife with helping him to overcome his drug addiction, praised his wife and said that she was an "extraordinary, pure and a beautiful light", suggest reports.

"I want to make a special dedication, about this time eight years ago we were about five days away from getting married. A few days before that my fiancee and I were talking about the wedding and she was worried about getting married to me - understandably - I was trying every way I could to reassure her that I was born to be her man...

"The only thing I could do was reassure her, comfort her, be strong. The next day, I happened to be with a friend of mine who was a songwriter and I was telling him what happened and he said we should write about that so I wrote this song for my wife and she`s here tonight," he said.

Urban then performed his track `Once In A Lifetime` during his concert on June 21.