The Twilight actor kept a low profile during the ceremony and didn't walk the red carpet, but he was pictured with his musician partner at the Warner Music official after-party.
FKA Twigs had been nominated for 'Best British Female Solo Artist' but lost out to Paloma Faith at the star-studded ceremony held at London's O2 Arena on Wednesday (25 February).
That didn't stop her partying up a storm with an adoring looking R-Pattz at the Freemasons Hall bash later that night.
Rob jetted into London to support FKA Twigs from the Oscars, where he was spotted at the exclusive Vanity Fair bash after the ceremony.
He and FKA Twigs began dating last year but have kept their relationship away from the limelight.
The full winners:
Best British Male Solo Artist – Ed Sheeran
British Group – Royal Blood
International Female Solo Artist – Taylor Swift
Best British Female Artist - Paloma Faith
BRITs Global Success Award – Sam Smith
International Male Solo Artist – Pharrell Williams
British Single – Mark Ronson ft Bruno Mars 'Uptown Funk'
International Group – Foo Fighters
British Breakthrough Act – Sam Smith
British Artist Video Award - One Direction
MasterCard British Album of The Year – Ed Sheeran 'X'
Critics' Choice – James Bay
British Producer Of The Year – Paul Epworth
Red carpet pictures!
Copyright: David M. Benett/Getty Images
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