The Philippines, which has been the world's biggest rice importer in recent years, is now overstocked with the grain and will likely cut overseas orders dramatically, the government said Tuesday.

National Food Authority (NFA) chief Lito Banayo said import orders by the previous administration had been extremely excessive, and hinted that corrupt officials may have been responsible.

"Our warehouses are filled. We are swimming in rice," Banayo told reporters at the presidential palace.

"I don't want to judge my predecessors. Whether culpability lies in incompetence or something worse, which is... corruption, the figures speak for themselves."

His remarks came after President Benigno Aquino said in a speech before Congress on Monday that the NFA had imported too much rice since 2004, with some of the grain left rotting in warehouses.

Aquino's criticism was part of a blistering condemnation of his predecessor, Gloria Arroyo, who he replaced on June 30.

Banayo, who was chosen by Aquino to head the NFA, said that because of the over-supply the delivery of 150,000 tonnes of rice from Vietnam had been pushed back from April to September.

The Philippines ordered 2.4 million tonnes of rice from abroad in 2009 but most of it was due for delivery in 2010, according to the NFA.

He said the government would likely cut imports next year if local rice production was strong.

"If we don't have a big storm, we will lower significantly our importation for next year," he said.

He reiterated Aquino's objective of achieving self-sufficiency in rice, describing it as "a national security issue".

Banayo said the excessive imports of recent years had pushed up the price of rice in the world market and left the NFA with a debt of 177 billion pesos (3.8 billion dollars).

Banayo said he ordered an audit to find the cause of the over-supply, and that he had asked Justice Department investigators to probe the orders.

Arroyo's former agriculture secretary, Arthur Yap, on Tuesday denied charges of excess imports, saying in television interviews that many government agencies were consulted before deciding how much rice to buy.