The Poker Face hitmaker kicked off her two dates in the British capital by taking the stage at the O2 Arena around 45 minutes late after rehears als overran, according to Britain's Daily Star Sunday .
The late start took the singer 25 minutes over her curfew, which is imp osed by bosses at the O2, and she could face a heavy fine from executives at the .
A source tells the newspaper, "Lady Gaga was still doing her dress rehe arsal at 7pm when the doors were supposed to be open and the first suppor t act was due on. She wouldn=E2=80=99t finish rehearsing until she was ha ppy.
=E2=80=9CIn the end she was 45 minutes late but refused to cut the set short. She told organisers she didn=E2=80=99t care about the fine, all sh e cared about was putting on the best show for her =E2=80=98little monste rs=E2=80=99.=E2=80=9D Lady Gaga's show was watched by a star-studded audience including Chery l Cole, Lily Allen, Sharon Osbourne and Emma Bunton.