Pre-1991 background

Both countries, each historically part of Kievan Rus' (9th to 13th centuries CE), came gradually under the control of the Polish–Lithuanian Commonwealth (1569-1795), and ultimately, of the Russian Empire (1721-1917). The Second Polish Republic ruled parts of each in the period from 1918 to 1939. Prior to the 1991 breakup, both countries formed part of the Soviet Union (founded in 1922) as the Byelorussian SSR (founded in 1920) and Ukrainian SSR (founded in 1919); they both became founding members of the United Nations in their own right in 1945. As Slavic nations, both Belarus and Ukraine share closely related cultures and are predominantly inhabited by the East Slavic ethnic groups of Belarusians and Ukrainians respectively.

There was an extensive period of diplomatic cooperation from 1918 to 1921 when the Belarusian Democratic Republic made contacts with the Ukrainian People's Republic (UNR) and the Ukrainian State of Pavlo Skoropadsky. Skoropadsky's government made the largest overtures to the Belarusians, with him himself informally recognizing the Belarusian DR as de facto independent in October–November 1918, although de jure recognition did not materialize. The UNR, although hesitant in the beginning, ultimately attempted to follow this route in international relations after Skoropadsky's fall. During this period, although without formal recognition, both countries established diplomatic ties in May 1918, exchanged diplomatic missions, the Ukrainians provided financial assistance to the Belarusian government and there were ideas of a federated defensive alliance between Ukraine and Belarus.^[1]

Breakdowns in relations

In August 2020, during the Belarusian protests against Lukashenko, Ukraine recalled its ambassador to Belarus for the first time to assess "the new reality" and prospects of further bilateral relations between the two neighboring countries.^[3] Belarus returned detained contractors (whom Lukashenko said were part of the Wagner Group) to Russia,^[4] coming in defiance of Ukrainian calls to send those who were detained to Ukraine to be prosecuted for their role in the War in Donbass. In a meeting with member of Ukraine's Verkhovna Rada Yevgeniy Shevchenko in April 2021, Lukashenko criticized former Ukrainian president Leonid Kravchuk for suggesting that Minsk be removed as a host in the Normandy Format as a result of the protests.^[5]

In response to the forced diversion of Ryanair Flight 4978 by the Belarusian government in May 2021, Ukraine banned Belarusian airlines from operating in Ukrainian airspace.^[6] In addition, Ukraine joined the European Union in imposing sanctions on Belarusian officials.^[7] In response to Ukraine, Belarus imposed new trade barriers on a variety of Ukrainian goods entering Belarus.^[8]

In February 2022, Russian troops invaded Ukraine from Belarus.^[9] Belarus has also stated that Russian nuclear weapons will be on Belarusian soil.^[10]