Glushkov, who had been sentenced in absentia in Russia to eight years in prison on embezzlement charges, died in London in mid-March. The UK police are treating the probe into his death as a murder inquiry. In Russia, an investigation has been opened as well.
READ MORE: Int'l Relations Expert on UK Salisbury Assessment: 'Accumulation of Fake News'
"We have to admit that London is refusing to cooperate [with Russia] on investigation into the strange death of former top manager of Aeroflot Nikolai Glushkov on March 12, leaking more and more versions comfortable for the Conservative government to mass media," the press secretary said.
On Friday, The Guardian newspaper reported that the UK police was also probing an earlier poisoning attempt on Glushkov, which occurred back in 2013.
READ MORE: Skripal Skeptics: Which Countries Didn't Agree With UK's Assessment of Case
Russia and the United Kingdom are also engaged in a dispute over the investigation of another incident — attempted poisoning of former Russian spy Sergei Skripal and his daughter Yulia in Salisbury — with London accusing Moscow of orchestrating the attack and Russia refuting all the allegations.