British intelligence services predicted there would be a "serious confrontation between Russia and Ukraine" all the way back in 1992, declassified files have shown, as reported on by Declassified UK.

Then-British Prime Minister John Major, only six months after the collapse of the Soviet Union, was being briefed by his team, and they were very avid in expressing their concern about the possibility of a war between Moscow and Kiev over Crimea. 

"Most of the population in Crimea is Russian," one of Major's advisors told him in a handwritten note as local Crimean officials were demanding a referendum on the peninsula's independence.

"If Crimea becomes independent, Ukraine’s ability to control the Black Sea fleet – based at Sevastopol – goes with it," Major's advisors warned him.

"The Ukrainians will try to prevent the referendum from being held…The issue will arouse passions among nationalists in Kiev and Moscow and could stir up inter-ethnic conflict within Crimea," Gordon Barrass, a senior UK intelligence official, underlined.

"There must be a real possibility that the situation will slip out of control. That could mean violence in Crimea, and serious confrontation between Russia and Ukraine," another intelligence official, Percy Cradock, underlined.

Crimea is a peninsula that lies on the bed of the Black Sea. It used to be under Russia's control until the Soviet Union gave it to Ukraine in 1954. However, Ukraine kept it until the end of the cold war and the collapse of the USSR, though with a notable Russian presence on it. It is of great value to Russia, as it houses its highly important Black Sea fleet.

Russia was able to gain Crimea again following a popular referendum in early 2015.