Wildfires raging in Siberia in record summer temperatures have decreased considerably over the past week, Russia's forest service said Saturday, as it battles blazes by cloud seeding and explosives.

Freakishly warm weather across large swathes of Siberia since January, combined with low soil moisture, have contributed to a resurgence of wildfires that devastated the region last summer, the European Union's climate monitoring network said this week.

Both the number and intensity of fires in Siberia and parts of Alaska have increased since mid-June, resulting in the highest carbon emissions for the month -- 59 million tonnes of CO2 -- since records began in 2003, it said.

Russia's Aerial Forest Protection Service said it was trying to suppress 136 fires over 43,000 hectares (430 square kilometres) as of Saturday. Firefighters are using explosives to contain the fires and using cloud seeding with silver iodide to encourage rain, it said.

However most of the fires have been deemed too remote and expensive to handle, with over 333,000 hectares currently ablaze in areas where all firefighting efforts have stopped, it said. This is considerably smaller than a week ago, when the service reported fires over a total of two million hectares.

From mid-June, regions in Russia's far north, including beyond the Arctic circle, have registered unprecedented heat records. Russia's weather service expert Roman Vilfand had said anti-cyclones -- which create abnormally clear skies with no clouds or rain -- had increased in the northern hemisphere.

In the Arctic, where the sun doesn't set in the summer, this means that sunlight is heating the Earth's surface around the clock, increasing risk of fires, he said. Fresh satellite images showed Saturday that the largest fires are still in Russia's vast Yakutia region, which is sparsely populated and borders the Arctic Ocean.

The region announced a state of emergency on July 2 due to the wildfires, which the governor of Yakutia said were caused by "dry thunderstorms." Greenpeace Russia's forest programme, which analyses satellite data, said Saturday that a total of 9.26 million hectares -- greater than the size of Portugal -- have been impacted by wildfires since the beginning of 2020.

The organisation blames Russia's wildfire crisis on lack of funding of the forest service which now cannot ensure adequate fire prevention.