Katy Perry on stage at London's O2 Arena on Monday nightKaty Perry appeared to be alluding to her rumoured romance with former Canadian leader Justin Trudeau with a comment she made on stage on Monday night.The Grammy-nominated singer is currently in the UK as part of her ongoing Lifetimes Tour, which most recently made a stop in London for a show at The O2 Arena.During the show, she told the British crowd that she was impressed with their energy, enthusing: “You’re like this on a Monday night after a whole day at work and a whole day at school?”“No wonder I fall for Englishmen all the time,” she quipped, referring to her past relationships with Russell Brand and