India’s monsoon rainfall this year was its lowest since 2018 as the El Nino weather pattern made August the driest in more than a century, the state-run weather department said on Saturday.

The monsoon, which is vital for India’s $3 trillion economy, brings nearly 70% of the rain the country needs to water crops and replenish reservoirs and aquifers.

Nearly half of the farmland in the world’s most populous nation lacks irrigation, making the monsoon rains even more vital for agricultural production.

The summer rainfall deficit could make staples such as sugar, pulses, rice and vegetables more expensive and lift overall food inflation.

Lower production could also prompt India, the world’s second-biggest producer of rice, wheat, and sugar, to impose more curbs on exports of these commodities.

Rainfall over the country during June to September was 94% of its long period average, the lowest since 2018, the India Meteorological Department (IMD) said in a statement.

The IMD had anticipated a rainfall deficit of 4% for the season, assuming limited impact from El Nino.

El Nino is a warming of Pacific waters that is typically accompanied by drier conditions over the Indian subcontinent.

The monsoon was uneven, with June rains 9% below average because of the delay in the arrival of rains, but July rains rebounding to 13% above average.

August was the driest on record with a 36% deficit, but again in September rainfall revived and the country received 13% more rainfall than the normal, the IMD said.

The erratic distribution of monsoon rains has led India, the world’s largest rice exporter, to limit rice shipments, impose a 40% duty on onion exports, permit duty-free imports of pulses, and could potentially result in New Delhi banning sugar exports.

The country is expected to receive normal rainfall during October to December, the weather department said, adding that temperatures were likely to remain above normal in most of the country during October.

Reporting by Rajendra Jadhav Editing by Helen Popper