Pakistan's prime minister has canceled his trip to the United States to attend next week's United Nations General Assembly, in order to deal with widespread floods at home.

Prime Minister Yousuf Raza Gilani's office said Friday that the Pakistani leader will coordinate relief efforts and begin visiting flood-affected areas on Saturday.

Pakistani Foreign Minister Hina Rabbani Khar will address the U.N. General Assembly in New York in the prime minister's place.

Monsoon rains have flooded large parts of Pakistan's southern province of Sindh. At least 230 people have been killed and more than 300,000 others have been left homeless.

Pakistani leaders were widely criticized for their response to last year's devastating floods, which killed more than 1,700 people and submerged one-fifth of the country. President Asif Ali Zardari made trips to Britain and France during the disaster.

Authorities say the recent flooding, which began in August, has destroyed or damaged some one million homes and has inundated nearly two million hectares of land. More than five million people have been affected throughout the country.

The United Nations World Food Program says it is rushing aid to Pakistan, after Prime Minister Gilani appealed to the international community for help.

The U.N.'s children's agency, UNICEF, says some 2.5 million children have been affected by the severe flooding in southern Pakistan.

The agency says it will distribute 200,000 liters of water to 40,000 people daily. An additional 40 tankers will be deployed in the next few days in order to increase the supply of clean drinking water and prevent the spread of water-borne diseases.

Meanwhile, the U.N.'s International Organization for Migration said Friday that it will launch an international appeal next week to provide emergency shelter and other non-food relief items to thousands displaced by the floods.