WASHINGTON

Russia's employment of hypersonic weapons as part of its ongoing military campaign against Ukraine has not fundamentally changed the conflict, Secretary of Defense Lloyd Austin said on Wednesday.

Testifying alongside Joint Chiefs Chairman Mark Milley, Austin said the Kremlin's forces have used hypersonics "several times" against Ukraine, but maintained they have not been "a major game changer to this point."

Hypersonic missiles are costly weapons that travel at least five times the speed of sound, making them difficult to track and intercept.

Asked specifically if Russia's use of the novel weapons increases the likelihood of the war devolving into a nuclear conflict, Austin said "it's very difficult to predict" what Russian President Vladimir Putin is thinking, but said he does not believe that is the case.

"He used hypersonic weapons weeks ago, and I think he's trying to create a specific effect with the use of that weapon," the defense chief told a House of Representatives subcommittee.

"He has options you know, he can launch a cyberattack, he can employ chemical weapons, those kinds of things that we're all on the lookout for, to see if he makes those kinds of decisions, but I don't think that that this necessarily takes him to the use of a nuclear weapon," he said.

Milley concurred with Austin's assessment, saying that while the weapons are markedly faster than earlier developed missiles "we are not seeing really significant or game changing effects."

He acknowledged that their use in Ukraine marks the first time they have been deployed in combat.