HAMBURG - Chicago wheat and corn fell on Monday as the first grains ship left a Ukrainian port using the newly agreed safe shipping channel, raising hopes Ukraine’s sea-borne cereals exports can resume on a large scale after being blocked by war.

Soybeans dropped on selling pressure after last week’s strength. Chicago Board of Trade most-active wheat fell 1.8% to $7.93-1/2 a bushel at 1056 GMT, corn fell 2.2% to $6.06-1/4 a bushel. Soybeans fell 1.6% to $14.45 a bushel.

A ship carrying grain left a Ukrainian port for Lebanon on Monday under a safe passage agreement, the first departure since the Russian invasion blocked Ukraine's sea shipping five months ago.

“Wheat and corn are being weakened today by the news that the first ship has sailed from Ukraine with grain exports using the safe shipping corridor raising the likelihood that we could see larger supplies of wheat and corn from Ukraine in the world market,” said Matt Ammermann, StoneX commodity risk manager. “The safe shipping corridor has been under negotiation for some weeks and the first ship has actually sailed despite a lot of doubt that an agreement would be reached, so this is an important step forward.”

Ukraine’s grain exports have been routed via land and river transport to eastern Europe, but traders stress ocean shipping is needed to significantly increase volumes. “Naturally the owners of ships trapped in Ukraine since February will want to get them out,” Ammermann said. “The next question is whether vessel owners will be willing to sail back into Ukraine to pick up grain shipments.”

Soybeans saw profit-taking after rises last week on concern about hot, dry weather stressing crops in the U.S. Midwest. “But the Midwest weather outlook has not changed significantly and hot, dry weather is again forecast this week," he added

(Reporting by Michael Hogan in Hamburg, additional reporting by Naveen Thukral in Singapore, Editing by Tomasz Janowski)