Floods and heavy monsoon rains have now killed 178 people and affected 1.5 million across Pakistan in the last three weeks, disaster management officials said Sunday in updated figures.

"At least 178 people have died and 1,503,492 others affected by recent monsoon rains and floods across Pakistan," a senior National Disaster Management Authority (NDMA) official told AFP.

He said that the rains had wounded 855 people, affected 5,615 villages and destroyed 20,312 houses all over the country.

On Wednesday the figures stood at nearly one million people affected and 139 dead.

Nearly 350 relief camps have been set up to help people, mostly in the central province of Punjab, the southern province of Sindh and the southwestern province of Baluchistan, the official said.

Further heavy monsoon rains are expected in Pakistan next month, but the NDMA is fully prepared, he said.

Pakistan, which has suffered from monsoon floods for the last three years, has been criticised for not doing more to mitigate against the dangers posed by seasonal rains washing away homes and farmland.

Streets in all major cities including Karachi, Lahore and Islamabad suffer intermittent flooding due to downpours, damaging roads and homes.

In 2010, the worst floods in the country's history killed almost 1,800 people and affected 21 million.