Russian grain exports risk dropping to a decade low in August due to shipping bottlenecks in southern ports caused by escalating attacks on commercial vessels in the Black Sea, industry analysts warned Tuesday.

Agricultural consultancy SovEcon projects Russia will export between 3 million and 3.4 million metric tons of wheat this month — well below the five-year August average of 5 million tons and potentially marking the lowest August total since the 2016–17 agricultural season.

Independent consultancy ProZerno, meanwhile, forecasts that overall grain exports will fall to nearly 2.5 million metric tons amid severe congestion across the Black Sea and the Sea of Azov. The five-year August average for grain exports is 5.7 million tons.

Russia, the world’s largest wheat exporter, and Ukraine, also a major agricultural exporter, have been attacking each other’s agricultural export facilities and commercial vessels in the Black Sea area in recent weeks, driving wheat prices higher on global markets.

The export logjam has left Russia’s domestic market oversupplied, driving local prices down by as much as 450 rubles ($5.46) per ton over the past week as farmers struggle to ship harvests abroad.