The 26-year-old 'Bad Romance' singer posted a picture of herself and 41-year-old Assange on her Little Monsters website but didn't add any caption to accompany the photo.
The star, who was launching her fragrance 'Fame' at Harrods in Knightsbridge on Sunday night, reportedly arrived at the Embassy at 7pm before sharing a meal with the Australian activist and leaving just after midnight.
Supporters acting as bail sureties to Assange, who is avoiding extradition to Sweden where he faces questioning over allegations of rape and sexual assault made by two women, were yesterday ordered by court to pay close to £100,000.
GaGa, dressed head-to-toe in black, made no comment as she left the building in central London.
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