India, the world’s biggest rice exporter, is considering more restrictions on its shipments of the grain as the nation grapples with rising food prices, a move that’s likely to further tighten global supply.

The government is considering imposing a tax on shipments of parboiled rice, according to people familiar with matter. No decision has been made yet and there’s no certainty deliberations will lead to the implementation of duties, said the people, asking not to be identified as the information is confidential.

Rice in Asia soared to the highest level in almost 15 years this month after the South Asian nation announced a ban on some exports and on concerns around the outlook for Thailand’s production. The government of India’s Prime Minister Narendra Modi has stepped up efforts to cool domestic food prices ahead of an election early next year, recently targeting the rising cost of onions.

A finance ministry spokesperson didn’t immediately respond to a request for comment.

India has already banned exports of broken rice and non-basmati white rice, curbed shipments of wheat and sugar, and restricted stockpiling of some crops. The nation is also considering abolishing a 40% import levy on wheat and selling tomatoes and grains from state reserves to improve supplies.

Rainfall in key rice growing states of West Bengal, Uttar Pradesh, Jharkhand, Bihar, Chhattisgarh and Andhra Pradesh has been 15% lower than normal so far this season, raising concerns about domestic supply. The staple is the nation’s biggest food grain crop that’s grown during the rainy season.