Major disasters like the Japanese earthquake and tsunami or Pakistan's floods are likely to become more frequent, and global governments must prepare for an uncertain future, according to a British report.

Paddy Ashdown, a member of the British House of Lords and ex-United Nations high representative to Bosnia and Herzegovina, said rich nations must help poorer countries to build up their defences against disasters.

In a government report published Monday, he said scientists believe recent natural disasters were not an aberration, but "the beginnings of a new kind of future in which mega-disasters are going to be more frequent."

"The scale, frequency and severity of rapid onset humanitarian disasters will continue to grow in the coming years, and at an accelerating pace," said the report issued by the International Development ministry.

Ashdown said a lack of prior support for Haiti and Pakistan worsened the impact of recent events.

'The scale, frequency and severity of rapid onset humanitarian disasters will continue to grow in the coming years, and at an accelerating pace.'—Paddy Ashdown, House of Lords

By 2015, the report predicts, roughly 375 million people will be affected by climate-related disasters every year, well above the 263 million believed to have been directly impacted by natural disasters in 2010.

Non-climate-related disasters such as earthquakes and man-made disasters are expected to affect many more.

Areas of the world most prone to natural disasters tend to be economically underdeveloped, which may exacerbate the death toll. On average, 1,052 people die from natural disasters in less developed economies, the report said, compared to an average death toll of 23 in fully developed economies.

The global trend toward urbanization will also have an impact.

"More people will be living on marginal land, in overcrowded and poorly planned housing, lacking access to adequate water and sanitation," the report said.

Climate change is also expected to reduce crop yields, "sometimes catastrophically," which will also require a change in the way agencies plan to feed those affected.

The report was focused on determining how the British government can best deploy its aid dollars.