Millions of Pakistanis are still in need of assistance as they recover from the floods that inundated large portions of the country during what was one of the most challenging years for the South Asian nation, two senior United Nations officials stated today.

"With an estimated 20 million people affected by devastating floods, the country faced its biggest ever humanitarian crisis," Rauf-Engin Soysal, the Secretary-General's Special Envoy for Assistance to Pakistan, and UN Resident Coordinator Timo Pakkala said in a joint message.

"Millions of Pakistanis still require relief assistance and full recovery of livelihoods and infrastructure will take years," they added. "Through resilience and determination and with the support of national partners and the international community, the country will overcome this challenging period."

The floods that began in late July affected some 20 million people across the provinces of Khyber Pakhtunkhwa, Sindh, Punjab and Balochistan, and damaged schools, health centres, important infrastructure such as sanitation systems, bridges and roads, and destroyed croplands.

Earlier this month UN humanitarian chief Valerie Amos urged the international community to provide the resources needed to help those in need of vital assistance.

"There is a continuing need for a strong financial response and I want to see attention focused on this immense human tragedy," she told reporters following her second visit to the country since the disaster.

"This is an emergency which will continue for months to come, and considerable relief efforts will continue to be necessary alongside recovery activities and development work," she added.

The $2 billion appeal for aid for Pakistani flood victims made in September, the largest-ever launched by the UN and its partners for a natural disaster, is currently 51 per cent funded.