FAO downgraded its forecast for the 2013 rice production in Philippines to 18 million tonnes from the expectation of a bumper crop of 18.9 million tonnes at the beginning of the season.

Crop losses in Philippines was estimated to stand at 110 million U.S. dollars while overall damage to the agriculture sector could exceed twice that figure, UN's Food and Agriculture Organization (FAO) was quoted as saying on Tuesday.

According to FAO's Global Information and Early Warning System (GIEWS), although rice production at the national level is likely to remain close to last year's level, the damage at the regional level is more severe.

FAO warned that farmers in areas hit by the typhoon could face severe food security and livelihood problems if they do not succeed in planting the next crop in the weeks ahead.

"Planting of the secondary season, mostly irrigated rice, was well underway and it is expected that crops are severely compromised. If we want to avoid entire regions of the country having to rely on food aid, we need to act now to help vulnerable families to plant or replant by late December," said Dominique Burgeon, Director of FAO's Emergency and Rehabilitation Division.

Hundreds of thousands of farmers in the Philippines whose crops were destroyed by Typhoon Haiyan need urgent assistance to sow new seeds before the end of the current planting season, said FAO.

In addition to providing seeds and fertilizers, rebuilding agricultural infrastructure such as storage and irrigation facilities destroyed by Typhoon Haiyan is critical for the longer-term outlook for the regions' rice production, FAO stressed.