The Financial Times reported the information.The dramatic rise in war risk insurance reflects growing dangers in one of the world's most vital shipping corridors for grain and oil. According to Marcus Baker, head of marine and cargo at insurance broker Marsh, premiums have jumped from roughly 0.25-0.3 percent of a vessel's value in early November to between 0.5-0.75 percent this week.The spike follows a series of Ukrainian strikes on Russian infrastructure and tankers. Last Friday, Ukrainian drones hit two sanctioned oil tankers—the Kairos and Virat—near Turkey's Black Sea coast. These vessels are part of Russia's "shadow fleet," a network Moscow uses to circumvent Western sanctions imposed after the 2022 invasion of Ukraine.Russian-linked oil tankers have seen the sharpest insurance increases, followed by bulk carriers transporting commodities like grain. Another insurance broker reported that some clients have experienced price hikes exceeding 200 percent.The attacks have extended beyond the Black Sea region. A Turkish-owned tanker was damaged by explosions off Senegal's coast last week, prompting Istanbul-based Besiktas Shipping to suspend all Russia-related voyages. While Ukrainian involvement hasn't been confirmed, the incident has raised concerns that the war's risks are spreading globally."Nobody would have put Senegal on the map as a heightened war risk," Baker said, warning that such unpredictable attacks could drive insurance rates higher worldwide.Maritime security experts say tanker owners are increasingly worried, with some fearing that vessels engaged in legitimate trade are becoming targets. There are also concerns that Russia might retaliate by targeting Ukrainian grain and ammonia exports.Russian leader Vladimir Putin on Tuesday condemned the attacks as "piracy" and threatened to cut Ukraine "off from the sea entirely." Baker predicted that Russian escalation would likely push insurance rates even higher throughout the region.The situation represents a sharp reversal from the relative calm that followed the establishment of Ukrainian grain export corridors. "The Black Sea had been a bubbling point since Russia's full-scale invasion," said Jon Gahagan, president of maritime risk group Sedna Global. "Everybody is watching this with interest to see whether there's a wider escalation."Oleksii Izhak, an analyst at the National Institute for Strategic Studies and co-founder of the Consortium for Defense Information, stated that Ukraine has right to strike ships supporting Russia's war effort.