Editor's note: A previous version of this article said that Sergei Skripal's wife was injured in the poison attack. Skripal's daughter Yuliia, not his wife, was injured.
Russian leader Vladimir Putin said that there must be a "severe" response against foreign intelligence services that "directly" support Ukraine and seek to "destabilize the socio-political situation in Russia" in a video address published on the Kremlin's website on Dec. 20.
Putin has long accused Ukraine of being guided by foreign powers, especially the U.S., and has claimed that its actions are dictated by Washington.
While the U.S. openly supports Ukraine and provides the country with funding, weapons, and strategic military assistance, there is no evidence that U.S. intelligence services actively assist Ukraine on the ground, especially within Russia.
The comments came on Russia's Security Officer's Day. Putin congratulated them for their work, particularly in parts of Ukraine that Russia illegally annexed in 2022.
He also accused Ukraine of pursuing "state terrorism" by engaging in sabotage and targeted assassinations. He did not elaborate on the statement.
Ukraine occasionally acknowledges its involvement in various operations within Russia, although it does not take direct responsibility.
Ukraine's military intelligence (HUR) published a video on Nov. 30 saying that trains in the region around Moscow were disrupted at the end of November "as a result of a special measure implemented together with the resistance movement."
A pro-Russian former lawmaker, Illia Kyva, who was charged with treason in Ukraine, was assassinated in Moscow Oblast on Dec. 6. in a special operation conducted by the Security Service of Ukraine (SBU), according to the Kyiv Independent's source in law enforcement.
Russian intelligence is widely believed to be behind a significant number of operations in foreign countries to sow chaos and destabilize society.
Russian operatives have also assassinated perceived opponents of Putin's regime in foreign countries, such as the poisoning of Russian double agent Sergei Skripal in the U.K. Skripal and his daughter survived the attack, but an innocent passerby who found the poison was killed.