Britney Spears has done fiancé Jason Trawick "proud", he has revealed.

The pop star filmed her first set of auditions in Austin, Texas, as a judge on US X Factor alongside returning judges Simon Cowell and LA Reid and fellow newcomer Demi Lovato.

"Princess, we just completed our first weekend in Austin on X Factor. Just wanted to say I'm very proud of you and I love you so much. Congratulations," he said in a video message.

Britney - who revealed her engagement to Jason in December - responded via her Facebook page, saying: "Awww Love you too xoxo."

The 30-year-old, who has two sons with ex-husband Kevin Federline, revealed she was impressed with the initial X Factor auditions.

"Texas has a lot of talent - seriously! Loving @TheXFactorUSA auditions so far," she previously tweeted.

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