Deputy Prosecutor General Ivan Sydoruk said those providing the funds were aiming to destabilize the situation in the North Caucasus, and the rest of Russia's Southern Federal District in advance of the December 2 polls.
Sydoruk said: "It is clear that the gang underworld cannot exist without major financing," but that unfortunately "law enforcement structures have not yet been able to identify any of the sources of terrorist financing."
He said the issue has provoked grave concerns in the Prosecutor General's Office and that serious measures need to be taken to block the financing.
Sydoruk also warned that further terrorist attacks in the south remain likely.
He said 500 firearms and over 170,000 rounds of ammunition have been seized in the district since the beginning of the year, but that "this is only a small part of what militants possess."
Separatists in troubled Chechnya often hide in other republics of the North Caucasus region, including Kabardino-Balkaria, Ingushetia, Daghestan, Karachai-Circassia and North Ossetia.
The active phase of the Kremlin's anti-terrorism campaign in the area was officially declared over in 2001, but regular attacks by gunmen continue.
