Russia’s crucial diesel attack submarines may have to withdraw from the Mediterranean Sea as Moscow appears to have been kicked out of its naval base in the Syrian port of Tartus.

The new Syrian government terminated a 49-year lease on the base the Kremlin brokered with the Bashar al-Assad regime in 2019, according to Russian and Syrian media reports.

Two Russian cargo ships that had been waiting offshore for three weeks were tracked entering the port on Tuesday and Wednesday to begin a probable evacuation.

It marks a major loss for Russia. The port at Tartus has played a vital role as a hub for its military presence in the Mediterranean, which it has increased over the past decade to support its operations in Africa.

Russia effectively lost its military use of the port in early December, when its fleet withdrew 10 miles off the coast as Moscow-backed dictator Assad was overthrown after a lightning-quick rebel offensive.