Russia's Black Sea blockade is preventing most exports from Ukraine and exacerbating a food crisis in the developing world, particularly in Africa.

Driving the news: Secretary of State Tony Blinken accused Russia on Monday of "blackmail" and "exporting starvation and suffering." He claimed Moscow was blocking Ukrainian grain exports and hoarding its own domestic supply in order to generate backlash against Western sanctions.

Senegalese President Macky Sall, the current chairman of the African Union, took a different tone on Friday when visiting Putin, whom he addressed as "my friend Vladimir."

• Sall said he received assurances that Russia will "facilitate the export of Ukrainian cereals." He also noted that Western sanctions on Russia has "worsened the situation" by making it harder to buy Russian wheat and fertilizers.

Between the lines: Western leaders see the food crisis as one more reason to condemn Putin. But many African leaders, like Sall and South Africa's Cyril Ramaphosa, are attempting to appeal to him.

• African countries are now facing "a witches brew of financial, fuel and food crises" due to drought, the pandemic, and now the war in Ukraine, says Gyude Moore, a fellow at the Center for Global Development and former government minister for Liberia.
• Yes, but: "Since it appears like stifling global grain supplies is a part of Russia's response to the sanctions, it isn't clear that the Africans have enough leverage to sway the Russians from the path they're on," Moore says.

Breaking it down: Last year, Ukraine supplied 11% of the world's wheat exports, 12% of corn exports and 43% of sunflower oil exports, according to the U.S. Department of Agriculture, almost entirely via the Black Sea ports that are now blocked.

• Sending grain westward by rail requires reconfiguring railcars at the border to fit a narrower gauge. Meanwhile trucking capacity is limited, and there have been long queues at border checkpoints and nearby ports.
• Thus, millions of tons of grain are sitting in storage, and the backlog will likely grow much larger after the upcoming harvest — all at a time when East Africa is facing famine and food shortages are growing dire elsewhere.

The Kremlin has implied that if the sanctions are eased, it will be more willing to let Ukrainian exports through, leading to the "blackmail" claims.

• The sanctions have also made it more difficult for Russia to export grain and, crucially, fertilizers, though those problems appear to be at least partially resolved, per Reuters.

Meanwhile, the U.S. and Ukraine accuse Russia of expropriating grain from eastern Ukraine and exporting it for profit.

• The U.S. last month warned 14 countries, most of them in Africa, that Russia could be shipping stolen grain their way, according to NYT.
• Moore says the chances of African countries facing mass hunger turning away cheap grain are slim, particularly with the U.S. offering little in the way of aid.
• He notes that the U.S. scrambled to help Europe find alternatives to Russian gas, but it seems to be doing less to contain the fallout in Africa. Meanwhile, the other humanitarian crises befalling Africa are slipping down the global agenda.

The bottom line: The stolen grain underscores a larger tension in the global response to the invasion: Western leaders want countries to take a moral stand against Russia, but they have their own interests to consider.

Go deeper: Food protectionism is on the rise