The Kremlin has appeared to relocate 100 missiles from Belarus to mainland Russia as analysts fear a large-scale attack on Ukraine could be imminent, the Daily Mirror reported.

Experts warn that the S-300 and S-400 missiles on the move could potentially indicate Russian President Vladimir Putin's intention to shift momentum with a dirty bomb blitz following Ukraine's successful counteroffensive campaign.

"Whatever Russia has in mind to inflict on Ukraine, the Kremlin appears to be expecting retaliation on its own soil from Ukraine or the West," an anonymous Russian insider told the outlet. "Analysts believe with these missile moves done so rapidly, just prior to this week's massive bombardments, the two are interconnected.

"But more ominously, they may indicate that worse may yet be to come, and they are preparing for a big reaction to this activity," he continued. "There is talk of a dirty bomb."

The news comes in the backdrop of U.S. Joints Chief of Staff Chairman Mark Milley confirming Tuesday that 111 Russian missile strikes and 26 kamikaze drone attacks were recorded, stating that it "was likely the largest wave of missiles that we've seen since the beginning of the war."

Defense Secretary Lloyd Austin, speaking alongside Milley, also commented on the recent rocket misfire in Poland that killed two, which U.S. and NATO officials have preliminarily attributed to Ukraine as an accident.

Russia "bears ultimate responsibility" for the incident, Austin stated. Later, Milley re-upped the defense secretary's concerns, claiming Putin's regime is "imposing a campaign of terror ... on the Ukrainian civilian population in order to defeat Ukrainian morale."

"We're also working to secure more critical equipment to protect and repair Ukraine's energy infrastructure after Russia's indefensible attacks," Austin declared.

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