Earlier in the week, Williamson, in his address at the Atlantic Council, accused Moscow of aggression, cyber attacks and the political sabotage, Sputnik reported.
"An unusually belligerent rhetoric of Gavin Williamson … sheds light on the true motives behind the forced increase in spending by NATO countries, expected to reach $1.26 trillion in 2018," the embassy’s spokesperson said on Friday.
The embassy expressed regret over the UK stance and noted that such claims undermine constructive relations between the European states and are part of the Conservative party’s campaign against Russia.
Russian-UK relations worsened after the poisoning of former spy Sergei Skripal and his daughter Yulia in the UK city of Salisbury.