Those forward purchases come on top of roughly 9.6 million tonnes of rice already shipped out of India this year - in line with record 2021 shipments - and may reduce the amount of grain available for other buyers during the coming months as loading schedules fill.
"International traders pre-booked for the next three to four months and everybody opened LCs to ensure business continuity," said Himanshu Agarwal, executive director at Satyam Balajee, India's biggest rice exporter.
Normally traders sign deals for the current and next month.
Aggressive purchases from India could also reduce demand for rice from Vietnam and Thailand, the world's second and third-biggest exporters respectively, which are struggling to compete on price.
WHEAT BAN
India last month banned wheat exports in a surprise move, days after saying it was targeting record shipments this year.
It also put a cap on sugar exports.
India is not a top global wheat exporter, but it is the world's second-biggest sugar exporter behind Brazil.
Those export curbs led to speculation that India could also cap rice shipments, though government officials said India does not plan to because it has sufficient rice stocks and local prices are lower than state-set support prices.
India's wheat ban trapped a large quantity of the grain at ports because New Delhi only allowed contracts backed by LCs to depart.
"Normally people open LCs while they nominate a vessel. This time they opened LCs for all rice contracts that were pending, so in case there is a ban on exports, at least the contracted quantity is shipped out," Agarwal said.
India accounts for more than 40% of global rice trade.
PRICE ADVANTAGE
Overseas buyers are looking for Indian rice because it is far cheaper than rivals, said B.V. Krishna Rao, president of the All India Rice Exporters Association.
Indian 5% broken white rice is offered between $330 to $340 per tonne on a free-on-board (FOB) basis, significantly lower than Thailand's $455 to $460 a tonne and Vietnam's $420 to $425, dealers said.
Thailand and Vietnam are not able to compete with India and they are trying to explore ways to support prices, Thailand's government has said.
If India restricts exports, global prices could jump sharply, said a New-Delhi-based dealer with a global trading house.
"Indian rice is more than 30% cheaper than other destinations. Poor buyers in Asia and Africa would be forced to pay very high prices if India restricts exports. That's why there is a rush to buy Indian rice," the dealer said.
Bangladesh, China, Benin, Cameroon, Nepal, Senegal and Togo are key buyers of India's non-basmati rice, while Iran and Saudi Arabia are key buyers of premium basmati rice.
India exported a record 21.5 million tonnes of rice in 2021, compared with combined exports of 12.4 million tonnes by Vietnam and Thailand.
Panic buying by importing countries was expected after the rumours of the ban began circulating because no other country can replace Indian shipments, said a Mumbai-based dealer with a global trading firm.