More than half a million Russians have demanded the authorities do more to tackle vast wildfires in Siberia that environmentalists have dubbed an ecological catastrophe, but which officials have said would be “pointless” to put out.

Wildfires cover almost 3 million hectares of forest, an area almost the size of Belgium, according to the Federal Forestry Agency, and have prompted states of emergencies to be declared in five Russian regions.

Greenpeace said on Monday that acrid smog had wafted across Siberia as far as the Ural mountains, posing a threat to people’s health.

“The situation with the forest fires in Siberia has long ceased to be a local problem and has turned into an ecological catastrophe on the scale of the entire country,” Greenpeace wrote on social media on Monday. A petition circulated online by an ecologist from the Siberian city of Tomsk had garnered 724,000 signatures as of Tuesday calling on authorities to take tougher action and to declare a Siberia-wide state of emergency.

The petition has no binding powers, but its author hoped public pressure would translate into government action.

Firefighters are working to put out forest fires covering almost 100,000 hectares in Siberia’s Irkutsk and other regions, but other wildfires raging on 2.8 million hectares are only being monitored, the Federal Forestry Agency said on Tuesday.

Authorities have said they do not plan to expend resources on fighting the latter as they are mainly in remote, uninhabited areas — known as “control zones” — and therefore not a direct threat to people.

“This is a normal, natural phenomenon, it’s pointless to fight it and perhaps even in some places also harmful,” the governor of Krasnoyarsk region, Alexander Uss, was quoted as saying by RIA news agency on Monday.

Uss said sending firefighters would put their lives at risk because of thick smoke and the sheer remoteness of the fires.

Greenpeace, however, said the authorities were wrong to say the fires, which have been burning for several weeks, affected only uninhabited parts of the country.

“There are people there! The lines of the control zones fall in such a way that settlements fall within them,” it said.

Gigantic forest fires have regularly raged through the vast expanses of Russia’s Siberia, but the magnitude of this year’s blazes has reached an exceptional level with fears of a long-term impact on the environment.

As fires sweep across millions of hectares enveloping entire cities in black smoke and noxious fumes, environmentalists warn of a disaster threatening to accelerate the melting of the Arctic.

More than 3.2 million hectares (7.9 million acres) were in the grip of fires on Monday, mainly in the vast regions of Yakutia in the north and Krasnoyarsk and Irkutsk in Siberia, authorities said.

The fires, triggered by dry thunderstorms in temperatures above 30 degrees Celsius (86 degrees Fahrenheit), were spread by strong winds, Russia’s federal forestry agency said.

The acrid smoke has affected not only small settlements but also major cities in Western Siberia and the Altai region as well as the Urals such as Chelyabinsk and Yekaterinburg, and disrupted air travel.

“The smoke is horrible. I am choking and dizzy,” pensioner Raisa Brovkina, who was hospitalised in Russia’s third-largest city Novosibirsk, told state television. On Sunday, the smoke reached neighbouring Kazakhstan.

A “concentration of pollutants exceeding the norm” was recorded in several cities, including the capital Nur-Sultan, said the Kazakh meteorological service.

Aside from health fears for the local population, environmentalists warn the fires may accelerate global warming.

“The forest fires in the eastern part of the country have long stopped being a local problem,” the Russian branch of Greenpeace said in a statement.

“It has transformed into an ecological disaster with consequences for the entire country.” According to the environmental group, almost 12 million hectares were burnt this year, causing significant CO2 emissions and reducing the future capacity of forest to absorb the carbon dioxide.

“Then there is the added problem that soot falling on ice or snow melts darkens it, thus reducing the reflectiveness of the surface and trapping more heat,” the World Meteorological Organization told AFP in a statement.

Agencies