India said it may allow limited rice exports, a sign that a global supply crisis could start to ease, as Philippine traders held off purchases hoping for new crops soon from southeast Asia.

Despite that optimism, US rice prices surged almost five per cent as prospects of reduced output in cyclone-devastated Myanmar and a larger-than-expected purchase of rice by Malaysia raised fresh supply concerns.

India, the world's second-biggest rice exporter last year, banned shipments of all rice except the basmati variety in March, one of a series of protectionist measures worldwide that triggered a wave of panic buying.

'We are reviewing the situation and may allow limited exports,' Commerce Secretary Gopal Pillai said on the sidelines of a conference in the southern Indian city of Kochi, adding the government may also review an export tax on basmati rice.

Prices on the Chicago Board of Trade, however, remained stubbornly high.

'Supply worries have intensified with the Myanmar cyclone and the market is likely to continue to rise and probably test its record highs soon,' said a trader in Seoul, as US rice futures for July delivery rose 4.9pc to $23.495 per hundredweight.

Rice prices had eased slightly after hitting a record of $25.07 on April 24 on prospects of increased supply from Thailand, the world's largest rice exporter.

But trade sources said the cyclone that devastated Myanmar's Irrawaddy delta last weekend destroyed thousands of tonnes of rice that were in storage and thousands of acres in the agriculturally rich region were now not plantable.

Malaysia bought 500,000 tonnes of rice on Thursday, which traders said showed how aggressive rice buyers are at a time when world rice stocks were shrinking and demand for the food staple was soaring.

The Philippines has so far bought about 1.7 million tonnes of rice for this year but has said it will need 2.2m tonnes.