It was the largest crowd to fill Kiev’s famous Independence Square since the heady days of the Orange Revolution as Sir Paul McCartney played a concert intended to promote unity in Ukraine.

More than 200,000 fans braved teeming rain for McCartney’s first concert in Ukraine, organised by the billionaire businessman Victor Pinchuk. The same number again watched live broadcasts of Saturday’s performance on big screens in five cities around the country.

Many Ukrainians have grown tired of years of political squabbling and Mr Pinchuk – the son-in-law of Leonid Kuchma, the former Ukrainian President – said that the free concert was a “time to be together”. The crowds who cheered McCartney as he sang Back in the USSR were happy to take up the invitation but the respite was brief.

As the music faded from the “Independence Concert”, tensions within the former Soviet republic quickly came to the fore. Hundreds of pro-Moscow activists in Sevastopol defied a court ban yesterday to unveil a statue to the city’s founder, the Russian Empress Catherine the Great. There were scuffles as Ukrainian nationalists tried to stop the unveiling of the 6m (20ft) monument to what they see as a foreign occupier.

The city administration had blocked an attempt on Saturday to unveil the statue to mark Sevastopol’s 225th anniversary. Instead, it erected one to a 17th-century Cossack leader in what local media called a “monument war”.

The conflict over Sevastopol’s past is the latest chapter in the continuing divide between Ukraine’s largely pro-Russian south and east and its pro-European west, which has been evident since the 2004 Orange Revolution. The city is also the focal point of rising tensions between Kiev and Moscow over the fate of the Russian Black Sea fleet, based in the city.

President Yushchenko insists that Russia must leave the port in 2017 at the expiry of a 20-year lease signed after the collapse of the Soviet Union. Russia is increasingly demanding the right to stay in Sevastopol in what some in Kiev suspect is a campaign to destabilise Ukraine and thwart Mr Yushchenko’s drive to enter Nato, a move fiercely opposed by the Kremlin. Ukraine blacklisted Moscow’s powerful mayor, Yuri Luzhkov, last month after he declared that Russia had “a lawful right” to reclaim the port.

Ukraine is also facing another political crisis as the Government of Yuliya Tymoshenko, the Prime Minister, threatens to collapse. Her pro-Western coalition lost its narrow majority in parliament after two legislators resigned.

Some on Ms Tymoshenko’s side blame officials close to Mr Yushchenko, her coalition partner, for the crisis, claiming that there is a plot to undermine her leadership and wreck her chances of winning a presidential election next year. Some even suggest that Viktor Yanukovych, the pro-Russian former Prime Minister, could be in line for a stunning comeback in a new coalition with the party that supports the President, Our Ukraine.

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