the Burevestnik, amid Moscow's ongoing war in Ukraine. Experts say the very-long-range weapon aims to skirt Western air defences   with its terrain-hugging and low-flying capabilities, but its strategic impact is likely to remain limited for now. Putin announced the development of the missiles in 2018, well before Russia's 2022 invasion of Ukraine, and declared a successful final test on Sunday. Unlike classic missiles that are propelled by chemical fuel, the Burevestnik  -- or "storm bird" in Russian -- uses a nuclear reactor. The reactor heats the ambient air and expels it at high speed to generate  thrust, said Amaury Dufay, an expert at France's Strategy and Defence Studies Institute.

"This allows for considerably longer flight time and range," he said. "It's a bit as if you had a car engine that consumes less for each 100 km (60 miles)". During the last test on October 21, the missile flew for some 15 hours,  travelling 14,000 kilometres, meaning it can easily reach the United States. "Its aim is to fly for a long time, very low, between 15 and 200 metres (49 to 650 feet), which complicates detection," said Dufay. It might "take off in Russia, make a detour via Latin America and then reach North America via the south, through a side that might be less well defended by US missile defences." (Bssnews)