The test by the Defense Advanced Research Projects Agency (DARPA) took place as the US and its global rivals quicken their pace to build hypersonic weapons - the next generation of arms that rob adversaries of reaction time and traditional defeat mechanisms.

In July this year, Russia said it had successfully tested a Tsirkon (Zircon) hypersonic cruise missile, a weapon President Vladimir Putin has touted as part of a new generation of missile systems without equal in the world.

The US' free flight test of its Hypersonic Air-breathing Weapon Concept (HAWC) occurred last week, the Defense Advanced Research Projects Agency, or DARPA, said in a statement.

"This brings us one step closer to transitioning HAWC to a program of record that offers next generation capability to the US military," said Andrew Knoedler, HAWC program manager in DARPA's Tactical Technology Office. There is no target date for that transition, but Knoedler told Reuters, "We are readying...