"[They] left because 10 new families moved in. It is a normal rotation of diplomatic personnel. What is not normal is diplomats having to arrive in groups because our Western colleagues, including the United Kingdom, introduced so-called complex visa exchanges", the Russian ministry said on Telegram.
According to the release, the new rules entail that instead of the regular extension or replacement of individual foreign-stationed diplomats, foreign ministries now need to prepare and submit lists which then need to be approved by the host country.
Earlier in the day, a few Telegram channels reported that 10 Russian diplomats departed from London with their families, allegedly to preempt a persona non grata designation.