According to MANA, The Bosphorus strait, which runs through Istanbul, and the Dardanelles strait further south were closed to transit shipping due to poor visibility on Saturday morning, Turkey's coastguard authority said.
The straits are one of the world's most important choke points for the maritime transit of oil, carrying over 3 percent of global supply, mainly from Russia and the Caspian Sea.
The waterways, connecting the Black Sea to the Mediterranean, also carry large amounts of grains from Russia and Kazakhstan to world markets.