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The Moldova–Ukraine border, the official border between Republic of Moldova and Ukraine, was established after the dissolution of the Soviet Union. The length of the inland border is 1,222 kilometres (759 mi), of which 267 kilometres (166 mi) is fluvial (i.e., along rivers) and 955 kilometres (593 mi) is land border. About 454 kilometres (282 mi) of it constitutes the de facto border between Ukraine and the unrecognized breakaway republic of Transnistria.
The border runs from the northern Romania-Moldova-Ukraine tripoint in the northwest of the country, 4 kilometres (2.5 mi), from the Ukrainian village and border crossing of Mamalyha, Ukraine to Criva, Briceni, Moldova. It runs east until the city and border crossing of Mohyliv-Podilskyi, where it turns southeast and enters the channel of the river of Dniester. By the village of Nimereuca the territory of Transnistria begins, which ends by Purcari. Several kilometers further it turns west. By Basarabeasca District it turns south and runs until the southern Romania-Moldova-Ukraine tripoint near Galați, Romania and Reni, Ukraine, by Danube.
As of 2014 the border had 67 permanent official border crossings classified into three categories: international, for crossing by citizens of any state; interstate, for crossing only by citizens of Moldova and Ukraine; and local, for local border traffic. Of them, 25 crossings are along the territory held by the Transnistrian separatist regime and are not monitored by the Moldovan border guards. There is a unique disputed situation with the Moldovan village of Palanca, Ștefan Vodă. As of 2014 its territory abuts to Odesa Oblast of Ukraine in such a way that there is no way to travel to the southwestern part of Odesa Oblast from the rest of Ukraine by land without crossing Republic of Moldova.
Per the Ukraine Government's site as of 21 Sep 2017 "Foreigners and stateless persons enter Ukraine only when they have a passport and a certain type of visa, which is required by a current legislation or an international agreement, if there are no other requirements. Copies of passports, visas and other documents confirmed by a notary give no right to cross the state border."