Tehran, May 3 -- Iran has reportedly started cutting oil production as the US further tightened its naval blockade on Iranian ports, leaving exports stranded, storage sites filling up and tankers clustering off its main export hub.

The measures come as Washington steps up pressure on Tehran's energy lifeline, betting that choking off oil revenue will force concessions.

Iran, for its part, appears to be digging in - scaling back output while trying to keep the system running for as long as possible, reports Bloomberg.

A senior Iranian official said production is being reduced in a controlled way to avoid storage facilities reaching capacity. The cuts could affect up to 30 per cent of the country's oil reservoirs, though officials insist t...