Russian claims that Ukrainian military forces attempted a terrorist attack in Crimea are unverified, an EU foreign policy spokeswoman says, noting that the Organization for Security and Co-Operation in Europe has no access to the occupied peninsula.
"There has been no independent confirmation of the claims made by the Russian authorities," the spokeswoman says in a statement.
"We reiterate our condemnation and non-recognition of the illegal annexation of Crimea and Sevastopol by the Russian Federation," the statement says, stressing the European Union's "unwavering" support for Ukraine's territorial integrity and sovereignty.
"The EU calls for a peaceful resolution of the conflict, including in eastern Ukraine, where all parties - including Russia - must fully engage in the complete implementation of the Minsk [peace] agreements," the spokeswoman adds.
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Ukrainian President Petro Poroshenko has ordered the military to be on combat alert on the de facto border with Crimea and in the country's two easternmost regions amid heightened tensions with Russia.
Russian President Vladimir Putin met with the country's security council on Thursday to discuss further security measures to secure Crimea's land border with Ukraine as well as its surrounding waters and airspace.
Russian President Vladimir Putin on Wednesday vowed to take steps to ensure safety in Crimea, hours after Russian authorities accused Ukraine of attempting to attack critical infrastructure in the region with two Russians killed in related clashes.