Rihanna has admitted she feels insecure about her body after working alongside some of the world's top supermodels.

The 'Diamonds' singer - who recently finished recording her new album 'Unapologetic' which will be released on November 19 - performed at the pre-recorded annual Victoria's Secret Fashion Show in New York City yesterday (07.11.12) and admitted she plans to hit the gym after seeing models including Miranda Kerr, Doutzen Kroes and Adriana Lima's bodies up-close.

She told USMagazine.com shortly before filming the show: ''I need to hit the gym after seeing these girls. When I sing I'm going to suck in [my stomach] and arch my back and try to remember my songs at the same time.''

But she also told reporters she was looking forward to checking out the ''t*ts and ass'' at the star-studded event.

The 24-year-old singer performed on the catwalk alongside the underwear models and was pictured grabbing and touching them as they strutted past her on the runway.

Bruno Mars and Justin Bieber also performed at the show, which will be aired in the US on CBS on December 4.

Earlier this year the 'Rude Boy' hitmaker admitted she lost weight after her father Ronald Fenty told her she was getting ''too fat'' but later said she missed her ''disappearing butt''.

She explained while her rear used to be her ''favourite'' part of her body, she is having to work hard on getting it back and is ''eating everything'' in the hope of restoring her bottom to its former voluptuous glory.

She said: ''I'm working on getting my butt back. It used to be my favourite body part, but now it's disappeared!

''I'm eating everything. I've been eating ice cream and fast food and Italian food.''