Mariah Carey and Nicki Minaj feud was 'natural'

Mariah Carey and Nicki Minaj feud on 'American Idol' was inevitable according to their fellow judge Keith Urban because they are all so passionate about music

Keith Urban wasn't surprised by Nicki Minaj and Mariah Carey's feud on 'American Idol'.

The Australian singer - who is the third new member on the show's judging panel this season - said there was always going to be tension between the superstars because they are both so passionate about music and believes their falling out was inevitable.

He told People.com: ''First of all, it's four passionate people who really care about the artists. Secondly, it's four people who just got thrown onto a dance floor without any sort of choreography and were told 'dance together.' So some toes get stepped on - and we're figuring it out.''

The 45-year-old singer - who is married to actress Nicole Kidman, with whom he shares daughters Sunday Rose and Faith Margret - will sit between the two female judges on the panel this season.

Fellow judge Randy Jackson, who is the only remaining original star on the panel, also claimed there has always been issues of rivalry on previous panels, which included Simon Cowell, Jennifer Lopez, Steven Tyler, Ellen DeGeneres and Paula Abdul.

He said: ''Listen, since this show started there have been very different, distinct personalities. It's always been a very happy, funny, dysfunctional family.''

Mariah recently admitted she hopes her feud with Nicki will be good for the show's ratings.

The 42-year-old songstress - who went head-to-head with the 'Starships' rapper on the judging panel of the show last October, with Nicki at one point threatening to shoot the 'Hero' singer and filming having to be called off - has revealed she felt extremel! y unsafe after their argument and confirmed she hired extra security after it.

She said: ''It felt like an unsafe work environment. Anytime anybody's reeling threats at somebody, you know, it's not appropriate.''

''I'm a professional. I'm not used to that type of environment,'' before revealing that she hired extra body guards because she felt it ''was the appropriate thing to do.''

She added: ''Sitting there on the road with two babies, I'm not going to take any chances.''

The new series of the show begins on January 16.