Ukrainian drone strikes have brought shipping in the Sea of Azov to a near standstill, according to Reuters, disrupting a corridor that carries up to a quarter of Russia’s wheat exports and sending tremors through global grain and fuel markets. Drone strikes have knocked out a large share of refining capacity, prompting Moscow to ban diesel exports until the end of July, and rattling global fuel markets. In Russian-occupied Crimea, petrol has hit a record high.