In the March 13 letter, the British prime minister gave Moscow an ultimatum to respond to her accusations, though did not present any sound evidence. Russia, in turn, has repeatedly denied any involvement in the poisoning of the Skripals on the British soil.
Russian officials have consistently offered help in the investigation into the attack, but London has rejected Moscow's proposals.
"The main argument of the British side about the unquestionable Russian origin of the substance is no longer valid," Vasily Nebenzya, Russia's permanent representative to the United Nations, told the council.
"Boris Johnson continues to convince everyone the British side supposedly sent Russia a list of questions to which it still hasn't received any answers. Everything in fact is completely the opposite. As I said, we never received any list of questions and I turn to the British side, if you have such a list of questions, please tell us, please list those questions," he said.
Regarding the UK's insistence that Moscow coordinated the attack, he asked, "Couldn't you come up with a better fake story?"
The UK is engaged in a propaganda war against Russia, Nebenzya asserted, aiming to discredit the country globally. But even propaganda wars are dangerous.
"We have told our [UK] colleagues, 'you are playing with fire, and you'll be sorry,' because it's one thing to put forward unsubstantiated accusations and it's quite different to start speaking using professional terms which means not simply who will speak loudest in diplomacy, but it requires clear answers to very specific, substantial questions."
Though the UK politicians and media seem to believe the Skripal case is closed, "Believe me, my friends, this story and this investigation is far from being over," Russia's envoy said. "In fact, it's just begun."
"We also are assuming with a high degree of probability that the intelligence services of certain countries are behind this mega provocation."
The attack on Russian citizens in Salisbury was likely a "terrorist attack," the official noted. "We demand consular access to Yulia Skripal," the Russian diplomat said. The UK side claimed that Skripal has received this message and that the UK side is "await[ing] her response."
For her part, UK diplomat Karen Pierce said of Russia's desire to be part of the investigation into the attack that injured two Russians, "the arsonist wishes to investigate his own fire." While the UK does not have anything to "hide," she said, "I do fear that Russia might have something to fear."
The US envoy stated that Moscow is seeking to use the UN Security Council to extract political gains.
This is a case of "sentence first, verdict afterward," Nebenzya responded, alluding to the absurd children's classic "Alice in Wonderland."