The Southeast Asian nation, which consumes about 33,000 tonnes of rice a day and is one of the world's biggest importers, is grappling with tight supplies.
Many rice farmers work small plots, have no money to invest and often have large families that leave them little rice to sell on the market.
"We must work harder to grow what we need," Arroyo said, announcing hundreds of millions of dollars in projects for everything from high-yield seeds to irrigation to new roads and ports to transport farm produce.
She said some of the projects would be funded by foreign governments in the form of development aid to the Philippines, which has been one of the countries hardest hit by the sharp rice increases.
She did not provide a total cost.
World rice prices have surged to record peaks on production shortfalls, high demand and dwindling stocks, prompting importers to scramble to secure supplies.
Vowing to make rice "abundant, accessible and affordable", Arroyo told a national food summit that state banks would make an additional $479m available in agricultural credit while the government would provide slightly more than a half of that for irrigation and infrastructure projects.
Additional amounts would be provided for rice research and for seeds.
The government said earlier on Friday that rice prices surged 10.9 per cent in March from a year earlier, taking the month's annual inflation to a 21-month high of 6.4 per cent.
At retail, prices of some rice varieties have increased 30 per cent from a year ago, and the state's National Food Authority called in the army this week to help it distribute subsidised rice.
"It's difficult to find cheap rice now," Eutemia Garcia, a 60-year-old, said as she waited in line on Thursday in a poor neighbourhood of the capital for bags of NFA rice. The maximum any individual could buy was 3kg.
Soldiers armed with M-16 rifles were keeping the lengthy line moving, but there was no sign of tension.
Another woman, 77-year-old Flora Flores, said: "I'm happy because cheaper rice is available. If not for the NFA, we would have a hard time."
Arroyo said the government would keep cracking down on unscrupulous private traders amid allegations of hoarding as well as the illegal sale of government-subsidised rice at nearly double the recommended price.
She said it was essential to eradicate corruption in the agriculture sector, and that "friend and foe alike are (being) brought to account for their actions".