Iranian ships have had no significant problems with insurance coverage following the re-imposition of US sanctions, according to the director of the country's Shipping Association.

Vessels can ply routes in most areas and ports of the world, Masoud Polmeh told reporters.

The IRNA website cited him as saying that due to US threats, some overseas insurance companies offer their services until the vessels enter Iranian waters.

Two Iranian insurers are also involved: Kish and Qeshm.

About a third of a vessel's operating costs are related to fuel.

Polmeh called for Iranian state bunker subsidies to help boost domestic vessels.