Russian Foreign Ministry spokeswoman Maria Zakharova said on Friday that Moscow does not exclude the UK's involvement in attacks carried out by Ukraine.
"We do not exclude that the British participated in the planning, organization, and support of terrorist attacks carried out by the Kyiv regime on the territory of Russia," Zakharova said in a statement, published on the ministry's website.
She added that London consistently supports Kyiv through arms deliveries, training of military personnel, providing intelligence, consulting on the organization of sabotage operations, and sending mercenaries.
Zakharova said that last year, UK Ambassador to Russia Deborah Bronnert was summoned to the ministry over the UK's involvement in the attack on the Russian Black Sea Fleet.
She said the UK was "strongly protested about the active participation of British military specialists in the training and supply of units of the special operations forces of Ukraine, including for the purpose of conducting sabotage operations at sea.
"Specific facts of such activity in London were given, specific names of British accomplices in this terrorist attack were named."
The spokeswoman stressed that the Russian side reserves the right to take "an adequate response, where and when it is deemed necessary."
"All responsibility for the consequences of London's destructive activity lies entirely with the authors and perpetrators of these reckless acts," she stressed.
Zakharova called the breaking of diplomatic relations "an extreme measure," noting that it cannot be ruled out "taking into account "the entire combination of factors."
