The State Duma on Wednesday gave two of the country's biggest energy monopolies the right to form armed units to patrol oil and gas pipelines, the country's economic lifeline.
A bill, backed by 341 deputies in the 450-seat Duma, gives state-controlled gas giant Gazprom and state oil pipeline monopoly Transneft the right to employ and arm their own security units.
Deputy Gennady Gudkov, of the pro-Kremlin A Just Russia party, opposed the bill, saying it opened the way for the creation of corporate armies in the country.
Gazprom is already described by some observers as a state within a state: It controls some of the country's biggest media outlets, has a watertight grip on gas exports and owns the country's third-largest bank.
But the bill's authors said it was needed to help the firms protect their infrastructure against militant attacks.
"A couple of terrorist acts and an ensuing environmental catastrophe would be enough to immediately declare Russia an unreliable partner and supplier of energy resources," said Alexander Gurov, a United Russia deputy who helped draft the bill and made his name in the Soviet Interior Ministry fighting organized crime in the 1980s.
Gazprom owns all trunk pipelines transporting natural gas across the country and exporting it abroad. Transneft controls all oil and oil product pipelines.
Russia supplies almost one-quarter of Europe's natural gas and is the world's second-biggest exporter of crude oil, after Saudi Arabia.