President Vladimir Putin praised the return of Crimea to Russia before tens of thousands today during his first trip to the Black Sea peninsula since its annexation. The triumphant visit was quickly condemned by Ukraine and Nato.
The celebrations, which included a massive show of military muscle in the annual Red Square parade in Moscow and in the Crimean port of Sevastopol, came as Ukraine is struggling with its most serious political crisis in decades. Pro-Russia insurgents in the east are fighting the government in Kiev and preparing to hold a referendum on Sunday on secession.
Mr Putin hailed the incorporation of Crimea into Russia as "return to the Motherland" and a tribute to the "historical justice and the memory of our ancestors". The peninsula of two million people had been part of Ukraine from 1954 until March.
His visit came as at least three people were killed today in a clash between government forces and rebels in the eastern Ukrainian city of Mariupol and the police station in the Azov Sea city of nearly 500,000 was ablaze. An Associated Press journalist saw three dead bodies near the station, including one policeman.
The Donetsk regional administration said three people were killed and 25 wounded during the fighting.
But Ukraine's Interior Minister Arsen Avakov said in a statement that 20 "terrorists" and one police officer were killed in fighting that erupted when 60 gunmen tried to capture the police station. He said they were rebuffed by police and the military.
Back in Crimea, Mr Putin boarded a boat, sailing past a line of Russian Black Sea Fleet ships anchored in Sevastopol's bay and greeted their crews before watching a flyby of 70 military aircraft. Residents flooded the city's streets to watch.
With minutes, Ukraine's Foreign Ministry protested that Mr Putin's visit trampled on Ukraine's sovereignty and international law, comments echoed by Nato Secretary General Anders Fogh Rasmussen.
"We consider the Russian annexation of Crimea to be illegal, illegitimate and we don't recognise it," Fogh Rasmussen told reporters in Tallinn, Estonia. "We still consider Crimea as Ukrainian territory and from my knowledge the Ukrainian authorities haven't invited Putin to visit Crimea, so from that point of view his visit to Crimea is inappropriate."
Victory Day is Russia's most important secular holiday and a key element of the country's national identity, honouring the armed forces and the millions who died in the Second World War. This year it comes as Russia is locked in the worst crisis with the West since the end of the Cold War.
Earlier in Moscow, Mr Putin watched as about 11,000 Russian troops proudly marched across Red Square to the tunes of marches and patriotic songs. They were followed by columns of dozens of tanks and rocket launchers as 70 combat aircraft, including giant nuclear-capable strategic bombers, roared overhead.
In another sign of triumph, parading troops on Red Square included a marine unit from the Black Sea Fleet, which flew the Crimean flag on its armoured personnel carriers.
The parade, which featured massive Topol-M intercontinental ballistic missiles, comes a day after Mr Putin visited the Defence Ministry's main operational centre to watch a massive military exercise that simulated a retaliatory nuclear strike in response to an enemy attack. The official statements describing the manoeuvres were strikingly blunt, reflecting simmering tensions with the West.
The West and the Ukrainian government accuse Russia of fomenting the unrest in Ukraine's east, where insurgents have seized government buildings in a dozen of cities and towns. The insurgents have set a referendum on independence for Sunday, a vote similar to a poll that paved the way for Moscow's annexation of Crimea in March.
Mr Putin's surprise call on Wednesday for delaying the referendum in eastern Ukraine appeared to reflect Russia's desire to distance itself from the separatists as it bargains with the West.
But insurgents in the Russian-speaking east defied his call and said they would go ahead anyway. While reflecting the anger against the central government in Kiev shared by many in the east, the move also helped to back Moscow's denial that is had engineered the mutiny.
Ukraine's main eastern city of Donetsk was calm today as a handful of veterans gathered to commemorate Victory Day, carrying former regiment flags and playing old patriotic songs.
In the Black Sea port of Odessa, which last week was rocked by violent clashes between pro-Russia forces and supporters of the central government in which nearly 50 people died, police arrested a local politician and two pro-Russian activists accused of staging the riots. Authorities also beefed up security in the city, fearing more violence, and the local governor banned the public display of Russian flags.
In Kiev today, a fire in a cable tunnel briefly interrupted broadcasts of several television channels. Viktoria Syumar, a deputy head of Ukraine's National Security and Defense Council, called the fire an act of sabotage.
Mr Putin said Wednesday that Russia had withdrawn its forces from the Ukrainian border, but the Pentagon and Nato repeated again that they had seen no evidence of a pullback.
"We still don't have visible evidence of Russian withdrawal of troops from Ukraine's border," Mr Fogh Rasmussen told reporters today. "We've seen such announcements also in the past, without any withdrawal of Russian troops so we're very cautious. I would be the first to welcome it if Russian troops were pulled out."
Russia wants Ukraine to adopt a new constitution that would give broad powers to its regions, helping Moscow to keep the country's east in its orbit. It also has sought guarantees that Ukraine would not join Nato. Ukraine has rejected the Russian demands.
Swiss President Didier Burkhalter, who chairs the Organisation for Security and Cooperation in Europe, offered a roadmap for settling the crisis during his meeting with Mr Putin this week, but it hasn't been made public yet. The OSCE's Secretary-General Lamberto Zannier visited Kiev today.
The United States and the European Union have slapped travel bans and asset freezes on members of Mr Putin's entourage in response to the annexation of Crimea. They threatened to introduce harsher sanctions if Russia continues to destabilise eastern Ukraine and tries to derail the May 25 presidential vote.
Despite the sanctions, Mr Putin is set to travel to France in early June for a ceremony marking the 70th anniversary of the D-Day invasion that hastened the end of the Second World War, his first encounter with Western leaders since the start of the Ukrainian crisis