LONDON — Ships loaded with grain have departed Ukraine despite Russia suspending its participation in a United Nations-brokered deal that ensures safe wartime passage of critical food supplies.

The U.N. said Tuesday that three ships carrying corn, wheat and sunflower meal left through a humanitarian sea corridor set up in July. A total of 14 ships also sailed Monday following Russia’s weekend exit from the grain deal.

Future shipments are in doubt after the U.N. said vessels wouldn’t move Wednesday. Turkey is trying to broker a resolution. Analysts say Russia is likely using it’s withdrawal as a bargaining chip to get what wants from the deal, such as easing the way for its fertilizer exports.

Russia has announced plans to conduct its own inspections of ships that have already cleared the joint checks in Istanbul, but further details were not known.