Russia–United Kingdom relations, also Anglo-Russian relations, are the bilateral relations between Russia and the United Kingdom. Formal ties between the courts started in 1553. Russia and Britain became allies against Napoleon in the early-19th century. They were enemies in the Crimean War of the 1850s, and rivals in the Great Game for control of central Asia in the latter half of the 19th century. They allied again in World Wars I and II, although the Russian Revolution of 1917 strained relations. The two countries were at sword's point during the Cold War (1947–1989). Russia's big business tycoons developed strong ties with London financial institutions in the 1990s after the dissolution of the USSR in 1991. The two countries share a history of intense espionage activity against each other, with the Soviet Union succeeding in penetration of top echelons of the British intelligence and security establishment in the 1930s–1950s while concurrently, the British co-opted top Russian intelligence officers throughout the period including the 1990s whereby British spies such as Sergei Skripal acting within the Russian intelligence establishment passed on extensive details of their intelligence agents operating throughout Europe. Since the 19th century, England has been a popular destination for Russian political exiles, refugees, and wealthy fugitives from the Russian-speaking world. In the early-21st century, especially following the poisoning of Alexander Litvinenko in 2006, relations became strained, and since 2014 have grown increasingly unfriendly due to the Russo-Ukrainian War (2014–present) and the poisoning of Sergei and Yulia Skripal in 2018. In the wake of the poisoning, 28 countries expelled suspected Russian spies acting as diplomats. In June 2021, a confrontation occurred between and the Russian Armed Forces in the 2021 Black Sea incident. Following the 2022 Russian invasion of Ukraine, relations between the two nuclear powers collapsed entirely; the United Kingdom imposed economic sanctions on Russian outlets, seized the assets of Russian oligarchs, recalled its citizens and severed all business ties with Russia. Russia retaliated with its own sanctions against the UK and accused it of involvement in attacks against Sevastopol Naval Base, the Nord Stream gas pipeline and the Crimean Bridge. The UK is one of the largest donors of financial and military aid to Ukraine and was the first country in Europe to donate lethal military aid. Historical background Relations 1553–1792 The Kingdom of England and Tsardom of Russia established relations in 1553 when English navigator Richard Chancellor arrived in