Britain Athletics, 2016 London Anniversary Games, Queen Elizabeth Olympic Park, Stratford, London on July 23, 2016. Canada's Brent Lakatos crashes with athletes during the mens 1500m T54. (Photo by Eddie Keogh/Reuters/Livepic)

A lioness drinks after being fed by senior keeper Glynn Hennessy at ZSL London Zoo on August 10, 2016 in London, England. Today marks World Lion Day which highlights the first global campaign to celebrate the importance and plight of lions worldwide. (Photo by Carl Court/Getty Images)

Tube passengers take a selfie next to a London underground roundel designed for the launching of the Night Tubes on display at Oxford Circus underground station in London, Britain, 19 August 2016. The long delayed Night Tubes service launched on 19 August. The 24-hour service will operate on Fridays and Saturdays. (Photo by Hannah Mckay/EPA)

Archive: A group of people dressed as Santa Claus wait for the bus on December 1960, London, England. (Photo by Keystone-France/Gamma-Keystone via Getty Images) Modern Day: Passengers wait for busses in Holborn on November 24, 2017 in London, England. (Photo by Chris J. Ratcliffe/Getty Images)

Competitors perform at the World Irish Dance Championship on April 13, 2014 in London, England. The 44th World Irish Dance Championship is currently running at London's Hilton London Metropole hotel, and will host approximately 5,000 dancers competing in solo, Ceili, modern figure choreography and dance drama categories during the week long event. (Photo by Dan Kitwood/Getty Images)

(L-R) Poppy Delevingne, Model of the Year Cara Delevingne, Joan Smalls and Karlie Kloss pose in the winners room at the British Fashion Awards at London Coliseum on December 1, 2014 in London, England. (Photo by Pascal Le Segretain/Getty Images)

A police officer stands at a police cordon near the scene of a terror attack in London, U.K., on Sunday, June 4, 2017. A van swerved into Saturday-night crowds on London Bridge, before three men got out and went on a stabbing rampage through nearby bars. (Photo by Luke MacGregor/Bloomberg)

Londoners enjoy a “Silent Night” as Big Ben falls silent, London, UK on August 21, 2017. ose Allerston from Clapham, London said “After a stressful day in the office, I couldn't think of anything better than going home and climbing into bed – but when I saw this bed opposite Big Ben I just couldn't resist getting in for a snuggle”. (Photo by Imagewise Ltd/Rex Features/Shutterstock)