MANILA, Philippines -- The government could spend as much as about $570 million this year to keep subsidizing low-cost rice for the poor, the agriculture minister said Monday.

The government spent P10 billion in the first half of the year so that people could buy rice at about 41 US cents per kilo, or around half the market price, Agriculture Secretary Arthur Yap said.

"At the rate we're going, we would go up to P25 billion ($569 million) minimum, just for rice," he told reporters.

The Philippines produces only about 93 percent of the rice requirements of its 90 million people, a third of whom live on a dollar a day or less.

Yap said the rice farming sector was under pressure because of the high costs of oil-based fertilizer, which he said accounted for 30 percent of farmers' production costs.

"Fertilizer usage is down because of the high prices. We are studying its possible impact on production," he said.