Olivia Wilde is apparently tired of Justin Bieber exposing his newly defined abs, and decided to let him know via Twitter.

“Bieber, put your f—ing shirt on. (unless you lost all your shirts in a fire in which case my condolences and please purchase a new shirt),” Wilde tweeted on Friday.

Bieber was most recently spotted sans shirt after departing a concert in Birmingham, England last week. Arriving back at the hotel, the pop star quickly changed to go out on the town for the first of two London celebrations of his 19th birthday. British singer Ella-Paige Roberts-Clarke was reportedly sent a Rolls Royce escort from Bieber to take her to the festivities.

Part two of Bieber’s birthday celebrations caused him to write, “Worst birthday,” on Twitter. Apparently, the singer was upset by the fact that bouncers were not letting certain friends of his into the club who looked underage. "The funny moment when people believe I brought underage people to a club," he wrote on Instagram, adding, "I said my 'worst bday' but that was due to dummies pushing over my fans and being overly aggressive. Btw it wasn't the worst bday cuz all my friends from back home flew in I was just mad in the moment."

Rounding out his roller coaster time in the UK over the last few days, Bieber was booed by fans when he showed up two hours late to perform at a concert at London’s O2 Arena on Monday night.

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