According to some media reports, forest fires are approaching the secret nuclear arms plant in the town of Sarov.

"There is no threat to the facilities at the [Sarov] Federal Nuclear Center. Nor is there an environmental threat or a threat of explosion," Sergei Kiriyenko said.

He said around 3,000 people, four helicopters, four airplanes and 30 fire trucks were involved in putting out wildfires in proximity to the Sarov nuclear center.

He did not say how close the wildfires were to the nuclear center.

He said at the moment they had to deal with brush fire but "we must be prepared for forest fires and therefore expand the fire protection zone in the forest."

At least 40 people have died and over 2,000 have been left homeless by fires which have swept across the central part of European Russia. The wildfires have been sparked by temperatures up to and above 40 degrees Celsius (104 Fahrenheit).

The damage caused by the flames is estimated at over 4.6 billion rubles ($150 million).

Russian President Dmitry Medvedev earlier on Tuesday ordered Emergency Situations Minister Sergei Shoigu to draw up a special program to boost the firefighting service.

Medvedev said the program should also ensure sufficient numbers of vehicles and other means of transportation, including airplanes.

He said there was a pressing need to adopt "advanced firefighting equipment, modern fire safety systems."

On Monday, Medvedev introduced emergency measures in the seven parts of Russia that have been the worst affected by wildfires.

Emergency regulations are enforced in the Republics of Mari El and Mordovia, as well as the Vladimir, Voronezh, Moscow, Nizhny Novgorod and Ryazan provinces.

Prime Minister Vladimir Putin on Monday ordered the heads of Russian regions to "clean up their act" on wildfires, adding they would be held personally responsible for building new homes for the victims of wildfires.

He also demanded that officials tighten fire safety regulations.

"The irresponsible behavior of those who ignore the bans and violate elementary safety rules comes at too high a price for ordinary citizens," Putin said.