"I know for certain, that Shamil Basayev directly managed this operation," Lavrov said in an interview with Aljazeera on Friday. He did not, however, provide evidence.
Other Russian officials had said evidence linked Basayev to the attack on the school in a region neighbouring Chechnya, but Lavrov's statement is the clearest accusation against the prominent separatist leader so far.
Lavrov also said Russian officials' statements that there were Arabs among the attackers were accurate. So far, officials have not provided evidence publicly to support claims that about 10 of the hostage-takers were Arabs.
Basayev directly managed the
Beslan operation, says Lavrov
"The information that there were Arabs is confirmed, as is information that there were representatives of other nationalities, including, as I understand, Russians, a Ukrainian, Chechens, Ingush," the foreign minister told Aljazeera.
Lavrov said identifying bodies after the "bloody drama" that ended the three-day standoff at the school in the North Ossetia region was "not so simple", but that there was no reason to question statements that the attackers came from various ethnic groups.
Basayev has been involved in or has claimed responsibility for hostage raids and other attacks outside Chechnya during a decade of war and chaos in the region, including a 1995 attack on a hospital in Dagestan and a well-coordinated assault targeting police in Ingushetia - sandwiched between Chechnya and North Ossetia - in June.
Lavrov also laid indirect blame for the school seizure and other attacks on Aslan Maskhadov, another separatist leader who was elected president of Chechnya in 1997 after a Russian withdrawal left the region with de facto independence.
Maskhadov "openly stated that as long as Russia's policy in the North Caucasus remains unchanged, there is no avoiding terrorist acts. This is instigation of terrorism, if not confirmation of the fact he directed it all", Lavrov said.
"If Europe categorically refuses to hold any negotiation with bin Ladin, why should we, in Europe's opinion, have contacts with his followers and disciples?"
Russian foreign minister
He told Aljazeera any calls from the West for dialogue with Maskhadov, or others like him, could not be accepted because they would defy "the partnership that is developing between Russian and the United States, between Russia and Britain, and with other countries in the fight against terrorism".
Such negotiations would not end the war in Chechnya and would "mean the defeat of Russia in the war against terrorism", Lavrov said, adding that talks with Maskhadov would be like European leaders negotiating with Usama bin Ladin.
"If Europe categorically refuses to hold any negotiation with bin Ladin, why should we, in Europe's opinion, have contacts with his followers and disciples?" he said.