State Border of Ukraine

State Border of Ukraine (Ukrainian: Державний кордон України, Derzhavnyi Kordon Ukrayiny, for brevity - DerzhKordon) is an international boundary of the state territory of Ukraine. According to the Article 1 of the Law of Ukraine on the State Border it is a line and a vertical surface that stretches along that line, which define the boundary of territory of Ukraine over the land, water, and air space.

Protection of the State Border of Ukraine is conducted by the State Border Guard Service of Ukraine (on the Earth's surface) and the Armed Forces of Ukraine (in air and underwater). The border was officially established by the Law of Ukraine "On Legal Succession of Ukraine" (September 12, 1991) and "On State Border of Ukraine" (November 4, 1991).

Ukraine borders with seven countries: Poland, Slovakia, Hungary, Romania, Moldova, Russia, and Belarus. The total length of the Ukrainian border is 6,992.98 km (4,345.24 mi). In reality Ukraine does not have real established and ratified borders with Russia, Belarus, and Moldova (republics of the former Soviet Union). The borders with other countries were inherited from the Soviet border patrol service which was recreated into the Ukrainian after the fall of the Soviet Union.

In 1994, the Budapest Memorandum on Security Assurances promised, inter alia, that its signatories (the Russian Federation, the United States of America, and the United Kingdom) would respect Ukraine's existing borders.

Ukraine also exclusively leased until 2017 part of territory of Sevastopol municipality to the Russian Black Sea Fleet for its transition outside of Ukraine to Novorossiysk. In 2010 Kharkiv Agreements were ratified by both sides (Russian and Ukrainian), which extended the lease for addition 25 with optional five-year extension if necessary. The agreements were also part of the Russia–Ukraine gas disputes which sprang out onto the international scale.

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