Ukraine’s food exports have already been harmed by intensified Russian attacks on ports this month, which could lead to a significant drop in trade despite efforts to divert shipments to rail, a Ukrainian farmer’s union said on Wednesday.

Ukraine is one of the world’s biggest exporters of wheat and corn, and the number one exporter of sunflower oil.

A de facto Russian blockade early in the nearly four-year-old war worsened a global food shortage.

Most Ukrainian food exports have resumed since 2023. But this month has seen a surge in near-daily Russian attacks with drones and missiles on ports in the Odesa region, reducing export capacity.

As a result, the UAC union said some wheat exporters had already defaulted on contracts to deliver shipments this month.

According to UAC estimates, at least one of the three key export ports is either idle or operating at 20% of its capacity.

Logistics routes have also been damaged connecting the rest of Ukraine to Danube River ports, said the union.

River ports had helped to compensate for the loss of major seaports since early in the war.

“Russia is attacking our ports, reducing our export potential. Without deep water and river water, our exports will decline significantly,” UAC said in a weekly report.

“Some large traders are already beginning to sort out quotas at railway terminals, which means that some of our grain may be sent to the border,” it added.

According to UAC, as of December 22, only 375,000 metric tons of wheat had so far been exported, out of 1 million tons contracted for shipment during the full month.

For corn, 1.5 million tons have been shipped so far out of a contracted 2 million tons.

In the case of sunoil, 275,000 tons had been shipped out of a contracted 410,000 tons, and exports for the full month were not likely to exceed 350,000 tons.

“Some traders have defaulted (on wheat), and some contracts are being rescheduled for January due to insufficient capacity at ports,” UAC said.

In December last year, Ukraine exported 800,000 tons of wheat, 2.6 million tons of corn and 378,000 tons of sunflower oil.

The Ukrainian economy ministry said on Monday that total grain exports had declined to 1.82 million tons in December 1-22 this year, from 2.88 million tons in December 1-27 last year, mostly due to smaller shipments of corn and wheat.