Russia is deeply alarmed about US plans to deploy thousands of additional troops to NATO's eastern flank member Poland, slamming reports out of Washington as unacceptable and portending an escalation in the Ukraine war.

Russian Foreign Ministry spokeswoman Maria Zakharova said at a press briefing on Thursday that sending additional American soldiers to Poland "would result in escalation of tension across Europe" and that Moscow would be forced to take "retaliatory measures".

Given that some 5,000 troops are being moved there from Germany, she did acknowledge that reducing America's troop presense in Europe would overall be "rational, justified, and long-overdue" step toward stabilizing what she called an "imbalanced" security situation created by NATO and Western policies.

Weeks ago, the White House began threatening a significant and historic force reduction from Germany, following Berlin officials' repeat criticisms of the US-Israeli war against Iran. This was initially presented in media reports as part of a broader drawdown from Europe, but now it appears US forces are just being shifted around, and with 5,000 to be placed closer to Russia.

But these thousands more troops in Poland could induce Russia to respond with "military-technical measures." Zakharova in perhaps the most provocative part of her remarks warned that NATO is pushing the continent toward a "suicidal" conflict.

In total, some 10,000 US service members are stationed in Poland, on a regular rotation, and the new Washington deployment would see thousands more added to this - from among the 80,000 deployed across Europe.

Poland shares a border with Russia's Kaliningrad Region, setting off further concerns about targeting and drone activity: 

The deployment of additional US military forces to Poland could lead to a "qualitative escalation" of tensions between Russia and the West and force Moscow to take retaliatory measures, Russian Foreign Ministry spokeswoman Maria Zakharova said on Thursday.

Zakharova also said that the number of drone attacks on Russian territory from the direction of Europe and Northern European states was increasing.

Moscow has expressed concern that Ukrainian drones could be using Baltic or other countries' airspace to launch attacks on targets inside Russia, an assertion rejected by Kyiv and the three Baltic countries.

Warsaw has hit back, with Foreign minister Maciej Wewiór having told the Polish news agency PAP that allied troops in Poland were "a necessary reinforcement of NATO's eastern flank" as a result of Russia's aggression in Ukraine, and given the Kremlin's "escalatory rhetoric" towards the alliance.

Wewiór additionally said the "real source of escalation and tensions in Europe" remains Moscow's "unlawful and aggressive military actions" – and not legitimate measures taken by NATO countries to defend their populations and borders.