The sisters’ last duet in a TV studio was on Young Talent Time in 1986.
Their iconic performance of Sisters Are Doin’ It For Themselves saw the then teenagers covered in sequins and with gravity-defying ‘80s hair.
“We’re not going to be able to give nearly as good hair this time around,” Kylie said. “Or outfits, or anything like that. We literally can’t beat that. So we can only aim to honour it.”
The Minogues will perform 100 Degrees, a disco-influenced duet from Kylie’s newChristmas album.
“We’ve done a live performance together a few years ago, but as far as a TV-tastic moment, it’s been a long time,” Kylie admitted.
Dannii Minogue, a judge on The X Factor, said the sisters deliberately don’t perform together despite regular offers.
“Early on it was important to separate ourselves,” Dannii said. “Even now we save (duets) for something that feels right or special. I was watching the YTT Sisters clip on YouTube the other day.
“In fact, a lot of the views on YouTube would be from me and Kylie looking it up. We often just YouTube it and go ‘Hang on, we have to watch that again, it’s hilarious!’”
100 Degrees was written by Kylie about adapting to a winter Christmas in the UK after being raised in Australia and was inspired by Donna Summer’s vintage disco classics.
“There’s not enough party Christmas songs,” Dannii said. “Everyone has Christmas parties, but what music do you put on? This song is perfect for dancing to. And our X Factor performance is going to be all guns blazing. And by guns, I mean glitter guns. It’s going to be a very sparkly, very Minogue Christmas.”
After the elimination of Mahalia, Dannii is going into the grand final without a contestant to mentor.
“I haven’t not had a contestants in the finals in seven years of doing the X Factor, so it’s new to me,” Dannii said. “Now I’m the impartial judge. There better be a hell of a lot of sucking up, and all those comments can come back on them now!”
The Minogue sisters have performed together on stage in 1987 at the Young Talent Time I Say No concert at the Myer Music Bowl, singing the Pointer Sisters’ Twist My Arm. The most recent performance came with Dannii replacing Robbie Williams for the duet Kids at Rod Laver Arena in 2006.