The Pentagon's top general said on Wednesday that China is making significant advances in hypersonic weapons systems, which would be difficult for the US to defend against. 

Mark Milley, chairman of the Joint Chiefs of Staff, is the first top Pentagon official to confirm China's successful test.

"What we saw was a very significant event of a test of a hypersonic weapon system. And it is very concerning," Milley told Bloomberg TV.

He also addressed comparisons that have been made to early wins by the Soviet Union in the Cold War space race.

"I don't know if it's quite a Sputnik moment, but I think it's very close to that," the general said.

The Soviet Union launched the Sputnik satellite in 1957, which caught the US by suprise and led to fears it was falling behind technologically in an accelerating arms race.

Why are hypersonic weapons important?

Milley's remarks came days after the UK newspaper Financial Times reported that in July, the Chinese military had launched a nuclear-capable hypersonic weapon that orbited the earth before reentering the atmosphere and finally missing its test target in China.

Hypersonic missiles are designed to travel more than five times the speed of sound on a flight trajectory that makes them more difficult to detect and intercept. 

The technology is at the forefront of future warfare capabilities and the news of China's progress in this new arms race has been received with worry in the US.

The US is also working on hypersonic weapons, however, it has yet to test a weapon on the scale that Milley said China had achieved.  

"It's a very significant technological event that occurred... and it has all of our attention," Milley said.

China has denied that its test was for a weapon, saying that it had instead been testing a spacecraft.

Peace under threat in the Pacific

The US, Russia and North Korea have all also tested hypersonic technology, but the test carried out by China earlier in the year is said to have had a longer range.

Relations between Washington and Beijing have become tense in recent years as China extends its influence and pursues ambitions in the Pacific that have troubled key US allies in the region.

Pentagon spokesperson John Kirby refused to confirm China's hypersonic tests on Wednesday, but said that any major development in China's military capabilities does "very little to help decrease tensions in the region and beyond."

ab/wmr (AP, AFP, Reuters)