“It’s all nonsense, we have nothing to do with this,” he told journalists, the Interfax news agency reported.
Mr. Lavrov added that Russia had asked London for details of the substance used in the poisoning, but “had received an incoherent response” which he said amounted to a “rejection of our legitimate demands.”
Russia’s foreign ministry also summoned the British ambassador to Moscow on Tuesday, according to Russian media.
An array of foreign leaders and officials, however, have sounded alarm bells over the nerve-agent attack, which Britain has said was carried out using what is known as a novichok, a chemical produced by the Soviet Union in the 1970s and 1980s.
“It is extremely worrying that chemical agents are still being used to harm people,” Ahmet Uzumcu, the director general of the Organization for the Prohibition of Chemical Weapons, said in a statement. “Those found responsible for this use must be held accountable for their actions.”
Mr. Skripal, 66, and his daughter, 33, remained in critical condition in a hospital on Tuesday, more than a week after the poisoning. He had been working for Russian military intelligence but then became a double agent for Britain. When he was found out, he was sent to a Russian prison. In 2010, he was freed and sent to Britain in a spy swap.