Russia on Thursday said Britain has "never known such a disgrace as prime minister" after Liz Truss resigned as UK leader just weeks into her time in office.
"The catastrophic ignorance and the queen's funeral immediately after her audience with Liz Truss will be remembered," foreign ministry spokeswoman Maria Zakharova said on Telegram.
"Britain has never known such a disgrace as prime minister."
Relations between Moscow and London have deteriorated for years, over issues such as the 2018 poisoning of a former Russian spy in Salisbury. They have reached record lows since Moscow's offensive in Ukraine.
The UK is one of Kyiv's staunchest supporters and Russia considers it as one of the most unfriendly Western countries.
Truss visited Russia as Foreign Secretary in February, just two weeks before President Vladimir Putin sent troops to Ukraine.
In a strained meeting with counterpart Sergei Lavrov, she confused two regions of Russia with regions of Ukraine.