"If Russia decides to attack any nation that's a NATO member, then that's a game changer," Austin was quoted as saying on Wednesday, when asked about a hypothetical scenario of Russian President Vladimir Putin launching an attack on Poland or another country in the region.
"But if you look at Putin's calculus, my view ... is that Russia doesn't want to take on the NATO alliance," he said during a hearing before the US House of Representatives' Appropriations Subcommittee on Defense, as quoted by Newsweek magazine.
"There are 1.9 million forces in NATO," Austin also said, adding that NATO has the most advanced capabilities of any alliance in the world in terms of aircraft, ships and other weaponry, Newsweek reported.
"So, this is a fight that he [Putin] really doesn't want to have and that would very quickly escalate into another type of competition that no one wants to see," he told the panel, according to the newsweek.com website.