Pakistan set for floods until at least month's end

No heavy rains are forecast this week, says Mahmood, but rivers are already swollen enough to continue to pose flood risks.

As for the waters already covering around a fifth of the country's surface area, they will not recede fully before the end of August, he said.

But at least the break in rain should allow aid agencies to reach more of the 20 million people affected by the floods.

Rescue workers warn there could be a "second wave of death" from exposure, hunger and water-borne disease as millions remain homeless and stranded by flood water.

International donors have already given more than half of the 350 million euros for which the United Nations appealed last week, according to UN spokesperson Maurizio Giuliano.

"But the challenges are absolutely massive and the floods are not over," he warned.

Only around 700,000 flood survivors have so far received food rations and drinking water, the UN estimates.

More than 650,000 families remain without even basic shelter, while some six million people are deemed to be at risk of contracting deadly diseases such as typhoid, cholera and hepatitis.

As the waters recede, the official death toll - which currently stands at 1,475 - is expected to rise as emergency teams begin to uncover the full extent of the damage.

The economic cost, too, is set to be high.

The World Bank estimates the cost of crops lost in the floods at one billion dollars (800 million euros), while the longer-term impact on soil quality could lead to yet greater losses.

Meanwhile the cost of reconstructing Pakistan's devasted infrastructure is set to rise to several billion euros. Rebuilding northern area alone will require two billion euros, according to Pakistan's UN envoy Zamir Akram.