The surge in strikes on Black Sea shipping has disrupted a major route for grain and oil exports from Russia and Ukraine. (AFP pic)LONDON: After seven strikes on cargo ships near Nato members Romania and Bulgaria last month, the US-led military alliance said it would deploy maritime patrol aircraft, radars and drones to bolster its eastern flank in the Black Sea.

Three days later, on Oct 23, another ship was struck just outside Romanian waters.

Last week, a Greek container ship was sunk by naval drones in Bulgaria's exclusive economic zone.

Unabating attacks show how the escalating maritime war between Russia and Ukraine is expanding into a major challenge for Nato in the Black Sea that has left littoral member states such as Romania and Bulgaria exposed.