The International Chamber of Shipping (ICS) is urging Indonesia to amend new rules that would impose cabotage restrictions on coal, palm oil and rice shipments.
Exporters must use Indonesian-flagged vessels and domestic insurance companies from the end of April.
There are, however, exemptions for foreign owners if Indonesian ships are limited or unavailable.
In a letter to Indonesia's trade minister Enggartiasto Lukita, ICS secretary general Peter Hinchliffe said: "The global shipping industry, which ICS represents, is very concerned that the decree appears to require that transportation of specified products and goods on international voyages, to and from Indonesian territory, must be conducted using Indonesian vessels.
