"This statement is a mixture of childish naivety and professional incompetence," Naryshkin said answering a question asked by Director General of the Rossiya Segodnya International Information Agency Dmitry Kiselev about May's plan to undermine the capabilities of the Russian intelligence in the United Kingdom.
The recent escalation of Russia-UK tensions started after the March 4 poisoning of Sergei Skripal, a former Russian intelligence officer, and his daughter in the town of Salisbury. May put the blame for the incident on Moscow and announced her decision to expel 23 Russian diplomats claiming that this would contribute to dismantling "the Russian espionage network in the United Kingdom."
Meanwhile, Russian Ambassador to the UK Alexander Yakovenko said that remarks made by UK Foreign Secretary Boris Johnson about alleged involvement of Russian President Vladimir Putin in Skripal's incident were "unacceptable."
Johnson earlier said that it was "overwhelmingly likely" that Putin personally ordered the attack on Skripal and his daughter in the Wiltshire city on March 4.
"Basically, I believe that this kind of statements are unacceptable for the Foreign Secretary," Yakovenko said in an interview with UK's Channel 4 television aired on Friday.
Moreover, the ambassador stressed that there was no evidence of Russia's involvement in the attack while the UK authorities block Russia's access to the investigation despite the fact that Yulia Skripal is a Russian citizen.