Paul McCartney [ tickets ]'s June 14 free concert in Ukraine's capital, Kiev, was the biggest ever in the post-Soviet republic, British newspaper The Guardian reported. The historic gig at Kiev's Independence Square was shown on giant screens in five cities across the country--reportedly in an attempt to promote unity in the bitterly divided region; the deep political divisions between the orthodox pro-Russian east and the Catholic pro-European West were further inflamed due to Ukraine's recent application to join NATO.McCartney took the stage in the midst of torrential rain, lighting and thunder, beginning his set with The Beatles' "Drive My Car," followed by a series of Beatles' songs, inevitably including "Back in the USSR." According to The Guardian, McCartney told the crowd, "I've been waiting a long time to say that."