Iran is facing the loss of a chunk of its oil export revenues as some of its largest trading partners in Asia plan to reduce their imports because of the pressure of US and European sanctions.

India, the second biggest buyer of Iranian crude after China, plans to stop importing Iranian oil from next month to avoid losing insurance coverage for its refineries, according to Asia-based oil traders. Japan and South Korea, two other big buyers, are set to reduce further their imports from April.

The combination could force Iran, which depends on oil exports for half its revenues, to cut oil production, which has already fallen to its lowest level in nearly 25 years. The drop in production, exports and revenues has contributed to the sharp drop of the rial against the US dollar.