Russian President Vladimir Putin has hailed the annexation of the Ukrainian region of Crimea during a visit, which coincides with the anniversary of the surrender of Nazi Germany to the Soviet Union at the end of World War II.
Putin sailed into the port of Sevastopol on Friday for the commemorations, his first trip to the region since it seceded from Ukraine and became part of Russia in March.
Watching a military parade, Putin said: "I am sure that 2014 will go into the annals of our whole country as the year when the nations living here firmly decided to be together with Russia, affirming fidelity to the historical truth and the memory of our ancestors."
"Much work lies ahead but we will overcome all difficulties because we are together, which means we have become stronger."
The visit drew swift response from Kiev, with Ukraine's foreign ministry calling it a "flagrant violation" of its sovereignty.
"Ukraine expresses its strong protest over the unapproved," visit of Putin, the statement said, adding that the Russian president "blatantly ignored Ukrainian legislation and international law".
"This provocation once again confirms that Russia deliberately seeks further escalation of tensions in Russian-Ukrainian relations and does not want to resolve problematic issues... through diplomatic channels."
NATO Secretary-General Anders Fogh Rasmussen also called Putin's visit "inappropriate".
"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,'' he said.
In Brussels, the European Union said Putin should not have used the commemoration of victory in World War II to showcase Russia's annexation of the region.
"The European Union notes with regret the presence of President Vladimir Putin at a military parade ... in Sebastopol, Crimea," Maja Kocijancic, spokeswoman for EU foreign policy chief Catherine Ashton, said.
"An important day in our shared history, dedicated to honouring the enormous sacrifices and giving remembrance to the millions of dead in the Second World War, should not have been instrumentalised to give visibility to the illegal annexation of Crimea," she said.
Meanwhile, the White House also warned that Putin's visit to Crimea would only exacerbate tensions.
"We do not accept Russia's illegal annexation of Crimea. Such a visit will only serve to fuel tensions," National Security Council spokesman Laura Magnuson said.
Deaths in Mariupol
Meanwhile, fighting erupted on Friday in Mariupol, a city of 500,000 on the Sea of Azov that is on the main road between Russia proper and Crimea.
An Associated Press journalist saw three dead bodies, including one policeman, near the police station.
|Al Jazeera's Nadim Baba reports from Sevastopol
The Donetsk regional administration said in a statement that 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 the fighting that erupted after 60 gunmen tried to capture the police station and were rebuffed by police and the military.
Avakov said the government was ready to negotiate with those in the east who wanted to sit down for talks but vowed to destroy those who took up arms.
He promised not to let Ukraine "turn into a burning buffer zone, where death will become the norm''.