Julianne Hough has been confirmed as the fourth judge on 'Dancing with the Stars'.

The 26-year-old professional - who has won the show twice - will join Carrie Anne Inaba, Len Goodman and Bruno Tonioli when the show returns for a 19th season next month and has vowed to be ''supportive'' and not ''mean'' to the competing couples.

She said: ''My role is to encourage and be supportive, and to also be candid and honest and try not to beat around the bush, to be too politically correct,

''I want to give critiques so they can improve. I'm not there to be harsh or cause a controversy. I won't be mean or malicious. That's not who I am. That's not my role at all.''

Julianne has previously been a guest judge on the show but felt the time was finally right to take a seat on the panel permanently.

She told People magazine: ''After being on tour with my brother [Derek], it felt like time to move on.

''I felt like I really reconnected with fans, and the people have supported me since day one. They have followed my from 'Dancing with the Stars' to my other aspirations. It just feels like the perfect time to reconnect and be a part of where it all began, with my family.''

And while Derek will be one of the professionals again this year, Julianne insists she will treat him and other show regulars, including Cheryl Burke and Mark Ballas, fairly.

She said: ''Derek has been known to be very good with his partnerships.

''But it's not about my brother, nor is it about Cheryl or Mark. It's about the partnership and the celebrity who is dancing.''

The celebrity dancers taking part this year will be announced on September 4.