With its southern ports under a US naval blockade, Iran is turning to the Caspian Sea and land borders for exports and imports, but falling water levels limit shipping.

BulletsIn

• Iran's southern ports are under a US naval blockade, and most of its maritime trade has traditionally moved through those ports.
• Tehran is looking to the Caspian Sea on its northern coast as an alternative route to export oil and import essential goods.
• The Caspian is the world's largest landlocked body of water, shared by Iran, Russia, Azerbaijan, Kazakhstan and Turkmenistan.
• An Iranian environment official said Caspian water levels have fallen by more than 20 cm a year over the past two to three years.
• Iran's northern ports could once berth vessels up to 6,000 tonnes but can now handle only 4,000-tonne ships, according to Iran's Shipping Association.
• Iranian ships entering the Caspian via Russia's Volga River have at times been stranded by low water levels.
• A China-Aktau-northern Iran route would move cargo by rail across Kazakhstan to Aktau, then by ship to Iranian Caspian ports.
• Iran is trying to complete missing sections of the Rasht-Astara railway, which would finish the western branch of the International North-South Transport Corridor.
• The corridor passes through Iran, Azerbaijan and Russia, and analysts warn the northward shift risks overreliance on Russia.
• Land borders are also strained, with up to 1,800 trucks reportedly queuing for days at the Norduz crossing with Armenia.