Russia–Ukraine border

The Russian-Ukrainian border is the international state border between Russia and Ukraine, which formally has been in existence since Ukraine's independence from the Soviet Union, on August 24, 1991. Over land the border outlines five oblasts (regions) of Ukraine and five oblasts of the Russian Federation.

Since the spring of 2014 the border has been compromised due to the 2014–present Russian military intervention in Ukraine. According to head of the State Border Guard Service of Ukraine Viktor Nazarenko Ukraine doesn't control 409.3 kilometers of the state border. This stretch of land is now controlled by the Donetsk People's Republic and Luhansk People's Republic.

In 2014, the Ukrainian government unveiled a plan to build a defensive walled system along the border with Russia, named "Project Wall". It would cost almost $520 million, take four years to complete and has been under construction as of 2015.

The border has inherited its location from the administrative territorial division between the Ukrainian SSR and the Russian SFSR. The first real demarcation took place in May 1918 in Kursk. After the fall of the Russian Empire, most of Ukraine (Ukrainian People's Republic) was overran by Red Guards of the Soviet Russia. With the help of Central Powers, Ukraine managed to recover all its territories of "Ukrainian governorates" and also annexed number of neighboring counties of Kursk and Voronezh governorates where ethnic composition of population was predominantly Ukrainophone (Ukrainian speaking). On 6 May 1918, a ceasefire agreement was signed in Konotop between Ukraine and the Soviet Russia. Between the fighting sides was created a neutral territory between 10–40 km wide to prevent further aggression, yet the Russian side decided to create some guerrilla forces which were transformed in two "Ukrainian divisions" (see Nikolay Shchors).

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