The Diamonds singer was announced as a musical guest at the annual catwalk extravaganza alongside Selena Gomez and The Weeknd back in October (15).

A week before the 20th anniversary show tapes in New York, it has been revealed Rihanna has dropped out to focus on making her eighth album, and Ellie has been drafted in as a replacement.

A representative for the underwear brand confirmed the People.com report on social media, but neither star has commented on the news.

Rihanna's father recently revealed her album is not ready for release and requires a lot more work because the pop star is not happy with the songs.

Ronald told Britain's The Sun newspaper, "Robyn is not happy with the new album... She's not comfortable with it. When she went over the songs she found all these little things she wanted to change and was worried about it. It's a long process and isn't easy.

"She has some things she likes but wants something more. To her it's not ready. She doesn't know which of the 26 songs to use. She's still looking for fresh material and has the energy for it."

Victoria's Secret supermodels Adriana Lima, Alessandra Ambrosio, Behati Prinsloo, and Candice Swanepoel are due to walk in the show, plus relative newcomers Gigi Hadid and Stella Maxwell, Miley Cyrus' rumoured girlfriend. Reality TV star Kendall Jenner is also gearing up to model lingerie on the runway, according to E! Online.

Lily Aldridge has the honour of wearing the 2015 Fantasy Bra, which features over 6,500 gems set in 18-karat gold and is worth $2 million (£1.3 million).

The 20th anniversary special is set to broadcast in the U.S. on 8 December (15).

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