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I am a UK citizen and I also have a Canadian passport. I am in the process of applying for a work visa in the US with my UK passport. I have an upcoming trip in Europe (I am currently in the UK). My question is: Will I be able to leave the UK with my Canadian passport (as I didn't enter the UK with my Canadian passport)? I'm slightly concerned there might not be time between getting back my passport from the US Embassy and my travel.