"So-called freak weather is becoming more common, and reducing vulnerability to unexpected extremes must be a top priority for governments," said Salvador Briceno, head of the U.N's disaster relief agency ISDR.

Separately, World Meteorological Organisation (WMO) chief Michel Jarraud, said the freeze that swept China from the north to its normally near-tropical southern provinces underlined the need for better seasonal climate predictions.

"The world needs to strengthen existing mechanisms that predict climate events and then ensure that this information is made available to all, especially to the benefit of people in developing countries," Jarraud said.

China's Meteorological Administration says the January extremes probably developed out of a La Nina -- or low sea- surface temperatures -- in parts of the Pacific in the second half of last year combined with unusual weather from the west.

MORE OF THE SAME

It is also warning that the country, now recovering as skies clear and power is restored from the freeze which killed scores of people, must be ready for more of the same as a result of global climate change.

Briceno said in a statement from ISDR headquarters in Geneva that China's sufferings underscored the need for all governments to build infrastructure that can withstand previously unthinkable weather.

"When billions of dollars in potential losses are balanced against the low costs of prevention in the future, the choices should be clear," he said. Most countries could expect to face similar situations in the coming years, he added.

Jarraud, speaking at a news briefing, said it was essential to ensure better seasonal -- as well as short- and long-term -- climate predictions if lives were to be saved and economies protected as weather patterns change.

Speaking after a three-day meeting of specialists on weather and disaster relief from a wide range of disciplines and international and national agencies, he said it was also vital to ensure better transmission of forecasts around the globe.

The meeting was called to prepare for a UN World Climate Conference in Geneva in the second half of next year which will focus on the science underpinning seasonal predictions -- an area in which Jarraud said there had been too little investment.