Pro-Russian crowds have seized two Ukrainian warships and Ukraine said its troops were being threatened in Crimea as the European Union considered new sanctions against Russia for its annexation of the Black Sea peninsula.
Tensions in the region remained high despite the release of a Ukrainian naval commander held by pro-Russian forces.
Shots were fired but there were no casualties as the Ukrainian corvette Khmelnitsky was seized in Sevastopol, according to a photographer at the scene. Another ship, the Lutsk, was also surrounded by pro-Russian forces.
The Defence Ministry had no immediate information on the incidents.
Ukraine’s deputy defence minister Leonid Polyakov accused Russian troops of constantly threatening to storm military bases where Ukrainian soldiers were located, according to the Interfax news agency.
In Geneva, Ukraine’s ambassador to the United Nations warned of a sharp deterioration in relations between the two neighbours, saying that Russia appears to be preparing for a military “invasion” in more areas of his country.
Ambassador Yuri Klymenko said there were “indications that Russia is on its way to unleash a full-blown military intervention in Ukraine’s east and south” since its annexation of Crimea. He said his statement was based on information from non-governmental organisations.
In an address to the German Parliament in Berlin, Chancellor Angela Merkel said the EU was readying further sanctions and that the G8 forum of leading economies had been suspended indefinitely.
Russia holds the presidency of the G8 and President Vladimir Putin was due to host his counterparts, including President Barack Obama, at a G8 summit in Sochi in June.
“So long as there aren’t the political circumstances, like now, for an important format like the G8, then there is no G8,” Ms Merkel said. “Neither the summit nor the format.”
The EU and the United States have slapped sanctions on individuals involved in what they say was Crimea’s unlawful referendum over joining Russia.
Moscow formally annexed Crimea earlier this week in the wake of the poll. The Black Sea peninsula had been part of Russia for centuries until 1954 when Soviet leader Nikita Khrushchev transferred it to Ukraine, and many residents were happy about rejoining Russia.
Russian forces effectively took control of Crimea some two weeks ago in the wake of the ouster of Ukraine’s pro-Russia president, Viktor Yanukovych, after months of protests and violence.
The crisis erupted late last year after Yanukovych backed out of an association deal with the EU in favoir of a promised $15bn (£9bn) bailout from Russia. That angered Ukrainians from the country’s pro-European central and western regions.
Ms Merkel said EU leaders would increase those “level 2” sanctions against Russia when they meet for talks in Brussels to widen the list of those whose assets are being frozen and who are banned from travelling.
She also reiterated that if things worsen, the EU is prepared to move to “level 3” measures, which would include economic sanctions.
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