The presenter caused a Twitter frenzy when she could not stop giggling and playing with her hair as she interviewed the singer, who is 15 years her junior.
Facing questions about the interview from The Mirror, she joked: “Who’s Alex?”
She went on: “I think it is a lot of fuss about nothing. It was another celebrity interview.
“BBC Breakfast will do the politics, the social issues and health issues and we also interview people who make great music or films. Those interviews by their nature will take on a lighter tone,” she explained.
Susanna - whose professional partner is Kevin Clifton - is quoted by PA as saying: "I find it really hard to remember the steps because it is not in my nature to memorise movements.
"I'm very much about the words and remembering words and images so I'm finding that I'm having to write everything down.
"At this stage I am petrified about that live show - there is so much to do - but also a little bit excited about it. But to be honest there's a lot of hard work between here and there."