U.S. says Russia is laying the groundwork to attack civilian ships and blame Ukraine

The TQ Samsun bulk carrier transits the Bosphorus Strait during the early morning hours on Tuesday in Istanbul. The TQ Samsun is the last grain ship, carrying corn and rapeseed, to leave Ukraine under the Black Sea grain initiative. (Chris McGrath/Getty Images)

The National Security Council says that Russia is attempting a "false flag operation" to "justify any attacks against civilian ships in the Black Sea and to then blame them on Ukraine."

The declaration comes days after Russia backed out of a deal that helped move grain from Ukrainian ports, threatening global food supply.