The United Nations secretary general, António Guterres, has visited several areas of Pakistan ravaged by floods, as he rounded off a two-day trip aimed at raising awareness of the disaster. Record monsoon rains and glacier melt in the country’s northern mountains have triggered floods that have killed at least 1,391 people, sweeping away houses, roads, railway tracks, bridges, livestock and crops. Huge areas are inundated, and hundreds of thousands of people have been forced from their homes. The government says the lives of nearly 33 million people have been disrupted. Pakistan estimates the damage at $30bn (£26bn), and both the government and Guterres have blamed the flooding on climate breakdown. The UN secretary general landed in Sindh province on Saturday, before flying over some of the worst-affected areas en route to Balochistan, another badly hit province. “It is difficult not to feel deeply moved to hear such detailed descriptions of tragedy,” Guterres said, after landing in Sindh, according to a video released by the office of the prime minister, Shehbaz Sharif. “Pakistan needs massive financial support. This is not a matter of generosity; it is a matter of justice.” A video released by the information minister, Marriyum Aurangzeb, showed Guterres seated next to Sharif as they viewed flood-damaged areas from an aircraft window. “Unimaginable,” Guterres said, surveying the damage. In July and August, Pakistan had 391mm (15.4in) of rain, or nearly 190% more than the 30-year average. Sindh province, in the country’s south, has seen 466% more rain than average. Guterres said on Saturday that the world needed to understand the impact of climate breakdown on low-income countries. “Humanity has been waging war on nature and nature strikes back,” he said. “Nature strikes back in Sindh, but it was not Sindh that has made the emissions of greenhouse gases that have accelerated climate change so dramatically. There is a very unfair situation relative to the level of destruction.”