Invasion of Ukraine may ultimately cost Russia access to Baltic Sea

President Putin's invasion of Ukraine has not only backfired by re-energising and strengthening NATO but may ultimately cost Moscow access to the Baltic Sea – a vital supply route between St Petersberg and the Russian enclave of Kaliningrad.

It is sandwiched between NATO members Poland and Lithuania, with the latter blocking Russia's only land access.

But an expert in naval affairs, seapower and maritime security says the maritime implications could cost Moscow much more.

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"The war is at a strategic turning point," maritime expert Dr Basil Germond said.

"On the one hand, it has now gone beyond the threshold for a short war and commentators are now talking about the risk of a war fatigue in the west, and the risk that the support to Ukraine will decrease.

"But there is another change, which is happening at the moment, very important, but less perceptible, it's the fact that the war, the maritime dimension of the war is intensifying.

"It's not just the war between two continental powers – Ukraine and Russia – it's the opposition between Putin's regime and the west – and the west is a coalition of seafaring and maritime nations."

Dr Germond added: "History has shown that when war becomes a long war it is much more likely to be won by a coalition of maritime nations and not by continental powers, like Russia, which lacks the ability to oppose in the long term the strategic effects of sea power."

Ukrainian forces are scoring notable successes in targeting Russian naval assets in the Black Sea using land-based weapons such as the Harpoon missile.