Russia and Ukraine together produce about 30 percent of the world's wheat exports.
Up to 25 million tons of wheat and other grain have been blocked in Ukrainian ports by Russian warships and landmines Kyiv has laid to avert a feared amphibious assault.
Despite Friday's retreat in wheat prices, analysts expressed skepticism about the accord's ability to sidestep the realities of the grinding Russia-Ukraine conflict amid doubts over Moscow's willingness to implement the deal.
"I'm still skeptical and I don't think I'm alone in that in questioning that it will actually move much grain," said Michael Zuzolo, president of Global Commodity Analytics & Consulting.
But Zuzolo said wheat prices may not have much further to fall, given that drought conditions are hitting output in some other parts of Europe.