ISLAMABAD - The United Nations on Thursday estimated 4.6 million people are still without shelter after Pakistan's devastating floods, tripling its target number for assistance as it prepared to drum up more aid.
The United Nations has described Pakistan's worst humanitarian crisis as one of the world's biggest disasters, but while foreign aid is now reaching some of the 20 million flood victims, critics have slammed the response as too slow.
At least six million survivors are dependent on humanitarian assistance to survive, in desperate need of food, shelter and clean drinking water, with concerns growing over potential outbreaks of cholera, typhoid and hepatitis.
"Roughly 4.6 million people are still without shelter," Maurizio Giuliano, spokesman for the UN Office for the Coordination of Humanitarian Affairs (OCHA) in Islamabad, told AFP.
The estimate includes hundreds of thousands of people who are still on the move, he said. Not all of them could be considered technically "homeless" because they may find homes to return to when the flood waters recede.
"In this context we have decided to increase the number of targeted beneficiaries for tents and plastic sheeting from the initial figure of two million to at least six million," he said.
At a camp for the displaced from across the country, survivors are battling with crippling heat, miserable sanitation and swarms of mosquitoes.
Many fled their homes with just the clothes on their backs and have been forced to drink contaminated water, causing watery diarrhoea.
The UN General Assembly meets in New York on Thursday in an effort to hasten the delivery of aid after receiving just over half of the 460 million dollars appealed for last week.
US Secretary of State Hillary Clinton is expected to use the UN meeting to announce extra American aid -- currently 90 million dollars -- after the floods wiped out entire villages, farmland and infrastructure.
"We still need more funds, tents, food, water and medical supplies," UN spokesman Martin Nesirky said.
A resolution urging the international community to help Pakistan recover in the medium and long-term will also be on the table, amid signs foreign donors are rallying in support of the embattled Muslim nation.
The Asian Development Bank said it would provide two billion dollars to repair roads, bridges, power lines, homes, schools, medical facilities and farm structures, and the World Bank has promised to lend 900 million dollars.
"The extent of human suffering caused by the floods cannot be easily quantified, nor can the damage wrought upon the country's physical and social infrastructure," said the ADB's chief for central and west Asia, Juan Miranda.
"But what is clear is that this disaster is like no other in living memory, and that our response must also be unprecedented, equal to the need and fast."
Although weather forecasters say the monsoon systems are easing off and water levels receding, the fallout from three weeks of devastating floods that have left nearly 1,500 people dead is likely to last for years.
Japan said it will send a military helicopter unit, expected to include more than 300 troops, to help with the relief effort and Pakistan's foreign ministry said Thursday that international assistance was gaining "momentum".
Senator John Kerry on Thursday became the first senior US policymaker to visit areas ravaged by the disaster, flying over affected areas in Punjab with Pakistani President Asif Ali Zardari.
Nuclear-armed Pakistan is on the frontline of the US-led fight against Al-Qaeda and is locked in battle with homegrown Taliban who have been blamed over a three-year bombing campaign that has killed more than 3,570 people.
A US government report warns that ecological problems would likely worsen due to climate change, threatening the unity of Pakistan and exacerbating the threat of Islamist extremists.
Islamabad has confirmed 1,475 deaths, but WHO representative Guido Sabatinelli told AFP he suspected the toll was much higher.
"We're talking about 20 million people affected today and there is no infrastructure and no health centres that can register the deaths," he said.