NATO’s top commander and U.S. Air Force Gen. Phillip Breedlove expressed concern March 23 at a Marshall Fund event in Germany over Russian combat troops continuing to mass on Ukraine’s borders; as well as a new buildup of Russian forces in the Trans-Dniester region in the breakaway Moldovan republic of ‘Transnistria’; an ethnic Russian enclave on the western border of Ukraine.
“Russian forces deployed on Moldovan and Ukrainian borders are very sizable and ready to enter from Trans-Dniester and into the eastern parts of Ukraine once the order is given.” - Gen. Phillip Breedlove
The general added that Moscow was acting more like an adversary despite NATO efforts to engage Russia as a partner.
The buildup of Russian forces in Transnistria is a new development. There have been Russian peacekeeping forces there for several years, following ethnic violence after the unrecognized republic broke away from Moldova twenty years ago.
This new concern however, follows the annexation of Crimea by Moscow, which brings Russian troops to within closer distance of Transnistria. Currently, the only line of supply and reinforcement is by sea.
Russian naval amphibious vessels have been closely tabbed transiting back and forth through the Turkish Straits to Syria from the Black Sea but, have since February been scarcely leaving the Crimea area. It is certain they were engaged in shifting Russian troops and armor to Crimea from Russia, however it is also possible an additional operation took place ferrying troops and armor to Transnistria.
Assuming that did in fact occur, then judging by Gen. Breedlove’s remarks there is reason on NATO’s part to believe an attack/invasion force is being built up on as many sides of Ukraine as Pres. Putin’s generals can muster troops, tanks and artillery on.
Ukraine is a large country geographically divided in half by the Dnieper River. Russian forces could invade and occupy eastern Ukraine fairly quickly, even without a secondary attack to break out of Crimea and link up with forces advancing overland from central Russia.
However, western Ukraine is some distance from Russia and Crimea, and has a natural defense line in the Dnieper River. Ukraine has concentrated the bulk of its ground forces in western Ukraine, with only a handful of combat formations east of the Dnieper.
Though sound military strategy, it can be negated and defeated if Russian troops are also able to advance into western Ukraine from points already established west of the Dnieper. To that end, Moscow building up forces in Transnistria to shift from ‘defense’ to ‘offense’ makes sense.
Transnistria, though narrow in width east to west, runs slightly over half the length of the Moldovan-Ukrainian border northwest to southeast.
Russian forces built up in enough numbers and firepower in Transnistria could attack in the direction of Odessa, to capture that sea port, and/or strike towards Nikolayev, Ukraine to link up with Russian troops advancing from Crimea via Kherson Oblast which banks the Dnieper River.
Such an advance and link up would quickly cut off Ukraine from access to the Black Sea. One lesson learned by Moscow during the 2008 invasion of Georgia was the 'annoyance' posed of delivery by sea of humanitarian aid. The mere presence of U.S. or other NATO flagged vessels, even civilian vessels, would be a complication Moscow does not want hampering military operations out of concern of hitting such ships.