The US is infuriated after China tested its supersonic nuclear delivery vehicle amid ongoing territorial tensions in the South China Sea.

The Chinese defence ministry has officially announced the glide vehicle, dubbed as Wu-14, was tested on Sunday – the fourth such test in 18 months.

Experts believe Wu-14 is a hypersonic cutting-edge technology vehicle capable of carrying conventional nuclear warheads by cruising and touching the edge of space.

"The scheduled scientific research and experiments in our territory is normal, and those tests are not targeted at any country and specific goals," South China Morning Post reported the Beijing's defence ministry as saying.

The Washington Free Beacon, which first reported the story, said that US experts are concerned about the frequency of the tests carried out by Chinese forces indicating the high priority of the project.

A US official said the latest test is "extreme manoeuvres" by the Chinese forces.

Earlier in November last year, a Congressional committee report on China said: "Hypersonic glide vehicles could render existing US missile defence systems less effective and potentially obsolete."