Mariah Carey performs 'When You Believe' with video of Whitney Houston

Mariah Carey kicked off her 'Sweet Sweet Fantacy Tour' in Glasgo, Scotland with a very special tribute for Whitney Houston.

Maraih Carey decided to perform their Oscar-winning duet 'When You Believe' from The Prince Of Egypt accompanied by footage of Whitney performing the beautiful track.

"This song is very special to me because I performed it with one of the greatest singers ever. She's no longer with us but she'll always be here. It's one of the songs that I'm so thankful that I had the opportunity to do ... a duet with Miss Whitney Houston. We got together and had an amazing time at the studio,"