According to the statement, Russian intelligence services are in contact with many Ukrainian politicians, including some former ministers and former Prime Minister Mykola Azarov. Azarov resigned in January 2014, amid large pro-European protests in the country. Ultimately, those protests led to the departure of the then pro-Russian president, who later fled to Russia.

A White House spokesman described the British allegations as “extremely concerning”. In a statement, the Russian Foreign Ministry said the reports are “disinformation” and “evidence that it is precisely NATO countries, led by the Anglo-Saxons, escalating tensions over Ukraine,” Russian news agency RIA Novosti reported.

Russia has amassed tens of thousands of troops on the border with Ukraine. Western countries fear a Russian invasion and have repeatedly warned President Putin of dangerous repercussions. Next week, British Prime Minister Boris Johnson will meet with leaders of the Group of Seven, the seven most powerful industrialized nations, on new sanctions against Russia. The Kremlin denies any plans to launch an offensive, but wants NATO forces to withdraw from Eastern Europe.