MOSCOW, Dec 12 (Reuters) - Russia is the global leader in hypersonic missiles and, by the time other countries catch up, is likely to have developed technology to counteract these new weapons, President Vladimir Putin said. Russia and the United States have an approximate parity when if comes to the number of warheads and their carriers, Putin said in comments aired on Sunday as part of a documentary film called "Russia. New History". "But in our advanced developments, we are definitely the leaders," Putin said, adding that Russia is also No. 1 in the world by the scale of upgrades of its traditional weapons. The president said that in the future, other world powers would possess similar hypersonic weapon technology. "When they get this weapon, it is highly likely will have means to fight this weapon." Putin said last month that tests of Russia"s Zircon hypersonic cruise missile are nearing completion and deliveries to the navy will begin in 2022. read more Some Western experts have questioned how advanced Russia"s new generation of weapons is, while recognising that the combination of speed, manoeuvrability and altitude of hypersonic missiles makes them difficult to track and intercept. They travel at more than five times the speed of sound in the upper atmosphere, or about 6,200 km per hour (3,850 mph). This is slower than an intercontinental ballistic missile, but the shape of a hypersonic glide vehicle allows it to manoeuvre toward a target or away from defences. Moscow"s military spending is much lower than that of Washington. Russia channelled $62 billion on military expenditures in 2020 versus $778 billion spent by the United States, according to the World Bank data. U.S. Air Force Secretary Frank Kendall told Reuters last month that the United States and China were engaged in an arms race to develop the most lethal hypersonic weapons. In October, the top U.S. military officer, General Mark Milley, confirmed a Chinese hypersonic weapons test that military experts say appears to show Beijing"s pursuit of an Earth-orbiting system designed to evade American missile defences. Putin spoke about Russia"s military power in the same documentary film where he lamented the collapse of the Soviet Union three decades ago as the demise of what he called "historical Russia". read more