British media said Russian diplomats had protested to the UK Foreign Office over the publication of Alexander Litvinenko's note, in which he accused President Vladimir Putin of orchestrating his death.
"If such reports were circulated, as you say, they are absolutely incorrect," Sergei Lavrov told journalists. "Diplomats were not given such instructions and could not have been given them."
The former security service agent, who defected in 2000, died of radioactive poisoning in London on November 23. As well as denying involvement in the poisoning, the Kremlin has also cast doubt over the authenticity of the deathbed message.
But the Russian foreign minister admitted he had told his British counterpart, Margaret Beckett, that it was necessary to avoid attempts to politicize the tragedy and excessive speculation on the matter.
Lavrov said fanning a scandal involving senior officials was inappropriate, and that such actions would inevitably damage Russian-British relations.
"If the English have questions, they should ask them via law enforcement bodies," the minister added.
The Foreign Ministry said earlier Monday that Russian visas had been issued for Scotland Yard detectives investigating the death of Litvinenko, who had received British citizenship in October.
Scotland Yard detectives are expected to travel to Moscow to interview several people who met Litvinenko around the time of his alleged poisoning at the beginning of November, including businessman and former KGB and FSB colleague Andrei Lugovoi.