Despite the Soviet Union having collapsed around three decades ago, the hammer and sickle could soon be flying back over Ukraine, America's top military official appears to have suggested amid claims about a Russian attack.

Speaking on Thursday during a visit to South Korea, US Defense Secretary Lloyd Austin demanded Moscow pull back its military from its Ukrainian frontier or face the hardest round of sanctions ever imposed.

When asked about which form the embargoes will take, he said that the "best methods" will be used, and that "whatever we do will be done as a part of an international community."

"The best case though is that we won't see an incursion by the Soviet Union into the Ukraine," the high-ranking official said, mistakenly referring to Russia as the former USSR - the collective of 15 republics that ceased to exist in 1991.

Ukraine and Russia were founding members of that country, which was led by Ukrainian politician Leonid Brezhnev for a large part of its existence.

Austin's remarks come amid heightened international concern that Moscow is supposedly amassing troops along its shared frontier with its neighbor, which has been seeking to join NATO in recent years.

On Wednesday, US Secretary of State Antony Blinken urged the Kremlin to de-escalate aggressions with Ukraine or face "severe consequences."

"We don't know whether President [Vladimir] Putin has made the decision to invade," Washington's envoy said, but alleged that "We do know that he's putting in place the capacity to do so in short order, should he so decide."

Moscow has consistently rejected accusations from NATO and Western news outlets that Russia is beefing up its military at the demarcation line with Ukraine. Kremlin Press Secretary Dmitry Peskov called such publications in the Western and Ukrainian media to be "hysteria."

He has previously insisted that Russia is not a threat, and that "the movement of our armed forces on our own territory should be of no concern to anyone."

(RT.com)