Fresh floods and landslides in northern Pakistan killed over 50 people on Saturday as aid workers struggled to provide relief to last week's flood victims across the country, DPA reported.
Geo television reported that 16 people died in Skardu district, kilometres north-east of Islamabad, as the floods caused by a new spell of heavy monsoon rain submerged dozens of villages.
Thirty-five others died in Kambra village of the same district due to landslides.
Rains hampered relief activities in the north-western province of Khyber-Pakhtunkhwa, where more than 1,600 people died last week and tens of thousands are still stranded.
Bad weather and poor visibility grounded the fleet of helicopters taking part in the aid operation.
The local administration in Khyber-Pakhtunkhwa's district of Nowshera issued a new warning of more floods and asked people to evacuate villages along the Kabul River.
Authorities also placed districts in southern Pakistan on alert.
"We have issued a red alert for five districts that are located along the Indus River and evacuation continues from the areas that we believe will be flooded," said Saleh Farooqi, director general of the Provincial Disaster Management Authority in Sindh province.
Some 500,000 people have already been moved from low-lying areas.
Earlier on Friday, the water coming from the north-western areas overflowed the banks of the Indus River and swamped 2,000 villages in six districts of Sindh.
The extent of the devastation was uncertain and differing figures were coming from local officials and UN organizations.
Nadeem Ahmed, the head of Pakistan's National Disaster Management Authority, told reporters on Friday that 12 million people were affected - three times higher than the UN estimate of 4 million victims.
Ahmed said that 650,000 homes have been destroyed or damaged, 557,000 hectares of crop land swamped and more than 10,000 cattle have died.
Ahmed said the country would need 2.5 billion dollars for relief and rehabilitation activities.
In his monthly radio address, Prime Minister Yousuf Raza Gilani appealed to the international community "to support and help Pakistan alleviate the sufferings of its flood-affected people."
Flood victims and opposition political parties have criticised the government for its sluggish response to the devastation. Growing public anger could be a source of concern for the unpopular civilian government that is fighting al-Qaeda and Taliban along its border with Afghanistan.
The prime target of the criticism has been President Asif Ali Zardari, who left the country in the middle of the crisis to visit France and Britain.
The president told the BBC that supervising relief activities was the prime minister's job, "and he's fulfilling his responsibility."