
Amid reports of Russia and China conductinghypersonic missile tests, US space force General David Thompson speaking at a security forum conceded that country has "catching up to do very quickly".
"We are not as advanced as the Chinese or the Russians in terms of hypersonic programs," Thompson was quoted as saying.
Thompson's comments come after General Mark Milley, chairman of the joint chiefs of staff called China's hypersonic missile test a "Sputnik moment".
"We have catching up to do very quickly, the Chinese have an incredible hypersonic program," Thompson said, adding, "It's a very concerning development ... it greatly complicates the strategic warning problem."
Watch:Russia tests Zircon hypersonic missile
A US Congressional report had earlier stated that Russia and China have "a number of hypersonic weapons programs" and have "likely fielded operational hypersonic glide vehicles - potentially armed with nuclear warheads."
On Thursday, Russia had test-fired a Tsirkon hypersonic cruise missile from the Gorshkov frigate amid tensions with the West.
Britain's General Nick Carter had warned an "accidental war" may occurbetween the West and Russia since "traditional tools and mechanisms" are no longer available.
The US report said, "China has also demonstrated a growing interest in Russian advances in hypersonic weapons
technology" while adding that "Chinese papers on hypersonic weapons include references to Russian weapons programs."
Read in Pics:With new hypersonic missile test in August, China surprised US officials
China had conducted two hypersonic missile tests in August. The hypersonic missile circled the Earth at low altitude and went undetected by US radars as it travelled over five times the speed of sound.Reports claimed it missed the target.
China however denied it had conducted the test asserting that it was a "routine test" of a space vehicle.
As relations between the West and Russia remain on tenterhook, Putin had recently told his defence chiefs to work on drone technology involving artificial intelligence with the "latest scientific and technological advances".
(With inputs from Agencies)