He was speaking as health officials warned that the death toll from the Pakistan floods will double in the coming weeks as 3.5 million children are exposed to cholera and diarrhoea.
Their forecasts, based on studies of other natural disasters such as the Indian Ocean tsunami, suggest that 1,400 people will die from water-borne infections.
Dr Guido Sabatinelli, the World Health Organisation's (WHO) representative in Pakistan, said aid workers were facing a “second crest” of fatalities.
“This is something that is very, very huge and we are lagging behind in where we need to be in terms of aid,” he said yesterday.
He added that 140,000 cases of cholera and other types of acute diarrhoea were expected in the next three months, of which 1% — or 1,400 — would prove fatal.
Yesterday, the Deputy Prime Minister also suggested donations from the public may be muted because they were “struggling to understand” the scale of the crisis.
Mr Clegg’s intervention came amid criticism that the international community has been too slow to provide aid for the estimated 20 million left homeless.
Britons have so far given £15m. The UK Government has also earmarked £31.3m in aid, nearly £17m of which has been allocated.
But the response has been lower than in the wake of the Haiti earthquake earlier this year, and the Disasters Emergency Committee (DEC) says more is needed as the situation is deteriorating.
The Irish government has donated less than half the amount it provided for the Haiti earthquake to the Pakistan flooding disaster.
But the Irish junior minister for overseas aid, Peter Power, said the €750,000 (£614,209) provided to Pakistan so far (compared to €2m for Haiti) was only an “initial amount”. He pledged that more aid would be committed.
“It's an unfolding disaster; it's happening in slow motion. It's not like the Haiti earthquake where 250,000 people died in a minute or the tsunami, where people were gone in a few minutes,” he said.
The State provided €2m (£1.64m) to the victims of the Haiti earthquake and €18m to the victims of the Asian tsunami.
UN Secretary General Ban Ki-Moon urged the international community to step up their aid pledges after visiting some of the affected areas yesterday, describing it as the worst natural disaster he had ever seen.
“The flooded area is the same size as England,” he said.
>More information about the relief effort available
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