Deputy Foreign Minister Volodymyr Ogryzko said: "Unfortunately, work unauthorized [by Ukraine] has been conducted in the Kerch Strait for several days." The ministry had already written to Russian diplomats demanding that Russia stop the work, he said.
Ukraine was, however, open to a constructive and mutually beneficial dialog with Russia, since "Russia has always been, remains, and will be our strategic partner," he added.
Kiev's displeasure with the dredging work, conducted by the dredger Urengoi to deepen the seabed, comes on the back of the dispute between Russia and Ukraine over a Black Sea lighthouse, in Ukrainian territory but leased by the Russian Black Sea Fleet, which Ukrainian officials seized five days ago. Ukraine said it had the rights to the lighthouse, while Russia's Navy Command called the move a "provocation".
Russia and Ukraine have an agreement authorizing Russia to lease the Crimean base at Sevastopol until 2017, but some Ukrainian politicians called for a revision of the contract terms after relations between the two countries deteriorated amid a row over gas supplies.
Ukraine's move recalls tensions in 2003 between Russia and Ukraine over Tuzla Island in the Kerch Strait, when Russia's attempt to construct a dam there provoked a bitter three-month dispute with its neighbor.