Russia’s grain-export pace is accelerating, just as Ukraine shipments are hit by uncertainty over whether the landmark Black Sea deal will be extended later this week.

Strong demand and competitive prices are spurring Russian shipments after a slow start to the season. It exported 6.53 million tons of grain and other foodstuffs by sea since Oct. 1, compared with 4.59 million tons over the same period last year, according to ship lineups from Logistic OS.

Meanwhile, flows from Ukraine are slowing as uncertainty looms over the extension of its safe-corridor beyond Nov. 19, when the original deal ends. Thirty-one crop-laden ships departed its Black Sea ports in the first 13 days of November, versus 90 over the same span in October, data posted by the United Nations show.

The agreement, struck in July and brokered by the United Nations and Turkey, revived seaborne exports from Ukraine after Russia blockaded the country’s ports following its invasion. The resulting grain backlog, coupled with a bumper harvest in Russia, has left the wheat surplus in the region nearly equal to that of all other major exporters combined. That means the sales trajectory is a key element for prices going forward.

“Everything apart from the Black Sea region is expected to be very tight, which will continue to influence the markets,” said Alexander Karavaytsev, senior economist at the International Grains Council.

The uptick in Russian shipments puts the country on track to retain its rank as the world’s top wheat exporter. Shippers and insurers had shunned its grain immediately after the war erupted due to concerns about breaking sanctions, and a strong ruble and export tax dampened sales. 

By contrast, the outlook for Ukraine has clouded, following Russia’s temporary stepback from the grain deal in late October. Some inbound vessels are still headed there, keeping grain moving as the deal’s deadline nears. But there is “virtually no demand” by importers for fresh seaborne shipments, analyst UkrAgroConsult said in a recent note.

Talks with the UN last week on extending the pact were “rather constructive,” a Kremlin spokesman said Monday. The text of the deal says it can be automatically extended for another 120 days when the initial run expires, unless a party notifies of their intent to terminate or modify it.

Ukrainian crops can keep flowing by rail, road and river even if the corridor shuts, but at much slower speed. Grain and oilseed exports for the season would reach a maximum of 35 millions if the corridor ends, at least 30% below the level if it continues, the Ukrainian Grain Association estimates. 

Chicago wheat and corn futures have eased from peaks earlier in the year, but remain poised for a sixth and fifth straight annual gain, respectively.

“It is important to continue the grain initiative in the Black Sea to make the ‘grain corridor’ work stably and predictably,” the Ukraine group said in late October. “This will help to avoid a global food crisis and another growth of grain prices on the world market.”