Russia says outgoing PM Truss was a 'catastrophically illiterate' disgrace
"Britain has never known such a disgrace of a prime minister," Foreign Ministry spokeswoman Maria Zakharova said in a social media post.
Truss has been the target of withering comments from Moscow since she visited in February as part of a fruitless drive by Western politicians to avert a Russian invasion of Ukraine.
The claim of illiteracy appears to refer to that trip, when Truss was British foreign minister. In a meeting with Russia's veteran foreign minister, Sergei Lavrov, she appeared to confuse two regions of Russia with Ukraine, triggering widespread mockery in Russian media.
Russian officials took a dim view of Truss's premiership from the outset and have revelled in her numerous gaffes. Upon her appointment in September, Lavrov said Truss did not know how to compromise and questioned how the British leader could say she did not know whether French President Emmanuel Macron was a "friend or foe."
Zakharova also on Thursday mocked Truss' high-profile photo shoot in Estonia last year, where she donned a flak jacket and helmet to ride in a tank during a visit to British troops stationed in the Baltic country.
Relations between Moscow and London had sunk to their lowest level in decades even before Russia invaded Ukraine, on the back of the poisoning of former Russian spy Sergei Skripal in the British city of Salisbury in 2018.