Brussels, November 6 (RHC)-- The Western military alliance, NATO, has suggested it might station permanent military units in its member states against what it calls 'threats' from Russia.

NATO Secretary General Jens Stoltenberg made the remarks on Thursday, signaling a potential transition from the policy the alliance has been maintaining vis-à-vis Moscow since 1997, when the two sides inked an agreement called the Founding Act on Mutual Relations, Cooperation, and Security.

Under the deal, NATO agreed to refrain from any "additional permanent stationing of substantial combat forces" that might alarm the Kremlin. "The important thing is that we have military presence," the NATO head, however, said, hinting that the past attitude might be changing.

Stoltenberg voiced 'concern' over Russian military presence in the Baltic, the Black Sea, and the Eastern Mediterranean, where the reinforcement is supporting Russia's weeks-long combat mission against terrorist groups in Syria.

Relations between Russia and NATO strained after Ukraine's Crimea region integrated into the Russian Federation following a referendum last March. On April 1, 2014, the military alliance ended all practical cooperation with Russia over the ensuing crisis in Ukraine.

The United States and its allies accuse Russia of supporting the pro-Moscow fighters in eastern Ukraine, and having supplied them with military aid, reinforcements, and resources. Moscow has denied the charges, saying any support from Moscow has only been of a humanitarian nature.