Rescuers are struggling to reach inundated areas where transportation and communications have been severed.

Peshawar, the area's largest city with population of three million, is cut off.

At least 60 people have died across the border in Afghanistan where flooding affected four provinces.

Mian Iftikhar Hussain, information minister for Pakistan's Khyber-Pakhtoonkhwa (formerly North-West Frontier) province, announced the latest death toll. Earlier, he described the floods as the province's worst ever.

Manuel Bessler, head of the UN's Office for the Coordination of Humanitarian Assistance (UNOCHA) in Pakistan, said about 1 million people's lives have been disrupted.

He could not say with certainty the full extent of the emergency in Pakistan, as he was having trouble reaching his own offices in some of the worst-affected areas.

UN aid workers were helping to co-ordinate efforts to provide shelter, health care, drinking water and ready-to-eat food rations, he said.

There was concern, he added, that swollen rivers running south would carry the floods to provinces like Sindh where heavy rain is forecast for the coming days.