The United States on Thursday targeted the financial network that it claimed funnelled Iranian cash to Houthi rebels to launch attacks on international shipping.

The US Treasury Department blacklisted a financier and three money exchange houses it said was behind the movement of millions of dollars from Iran via Turkey to Yemen.

The Iran-backed Houthi rebels have been held responsible for a dozen missile and drone attacks on Western shipping passing through the Red Sea, forcing some companies to re-route from the Suez Canal and travel via the Cape of Good Hope.