Turkmenistan's President has instructed experts to find way to finally extinguish a big five-decade-old fire in the "Gateway to Hell," a massive natural gas crater in the Central Asian country.

President Gurbanguly Berdymukhamedov spoke on state television on Saturday, urging officials to put out the fires at the Darvaza gas crater in the middle of the vast Karakum desert, citing environmental and economic concerns.

Berdymukhamedov had previously ordered researchers in 2010 to discover a solution to extinguish the fires that had been raging since a Soviet drilling operation went poorly in 1971.

He said that the man-made crater "negatively affects both the environment and the health of the people living nearby". 

"We are losing valuable natural resources for which we could get significant profits and use them for improving the well-being of our people," the president added in televised remarks. 

Here’s what you need to know

The crater was formed in 1971 when a Soviet drilling rig collided with a gas cavern, forcing the drilling rig to fall in and the ground beneath it to collapse.

The Soviets decided to set fire to the gas in order to prevent the toxic fumes from spreading.

Since then, the pit has kept burning, despite earlier attempts to extinguish it.

The resulting crater -- 70 metres (229 feet) wide and 20 metres (65 feet) deep -- is a popular tourist attraction in Turkmenistan.

The president formally called it the "Shining of Karakum" in 2018.