The catastrophic flash floods that devastated Nepal last month have given the government a renewed impetus to press its case for climate justice and compensation on the international stage.

Nepal’s prime minister, Balendra Shah, is due to address the United Nations General Assembly in New York on September 24, where he is expected to highlight the country’s vulnerability to climate change and demand greater international support after the deadly floods in Rasuwa, the foreign ministry said on Friday.

Shah will lead a high-level Nepali delegation to the 81st UN General Assembly, whose high-level general debate runs from September 22 to 28.

The decision to put the floods at the centre of Nepal’s international diplomacy comes as environmental campaigners, activists and sections of the Nepali media have increasingly framed the disaster as a question of climate justice. The government now intends to take that argument to the world’s principal diplomatic forum.

Nepal’s case comes at a difficult moment for the international climate-finance system. The United States has formally withdrawn from the Paris Agreement, while wealthy countries have continued to fall short of expectations over funding for vulnerable nations.

Nepal says it has secured $20 million in climate finance through a mechanism intended to support countries vulnerable to climate change. But the scale of the damage from the Rasuwa disaster dwarfs such sums. The government’s preliminary estimate puts the cost of rebuilding infrastructure destroyed by the August 26 floods at about $4.7 billion.

The floods, which swept through settlements and infrastructure along the Trishuli river, caused extensive loss of life and damage to roads, bridges, hydropower plants and other critical infrastructure. Their scale has already attracted international attention.

As of Friday, 1,385 bodies had been recovered, while 5,130 people remained missing.

Kathmandu nevertheless believes the disaster offers a compelling opportunity to demonstrate the consequences of climate vulnerability for a country that contributes little to global greenhouse-gas emissions.

Shah is expected to argue that countries such as Nepal should not be left to bear the costs of a crisis they have done little to create. He will call for greater international attention to climate-related loss and damage and press for timely and adequate compensation through mechanisms including the Fund for Responding to Loss and Damage.

He is also expected to urge wealthy and developed countries to make climate finance and technology more accessible and affordable, particularly for climate-resilient infrastructure, climate-smart agriculture and capacity-building.

Nepal will seek to broaden the argument beyond disaster relief, highlighting its own contribution to environmental protection through more than 46 per cent forest cover, its Himalayan ecosystems, extensive river systems and what the government describes as a nature-friendly way of life.

The country will reinforce that message with a UN General Assembly side event, “Sagarmatha to the Sea: A Call to Action for a Climate-Resilient Future”, focused on the effects of global warming on the Himalayas and the increasingly destructive consequences for mountain communities.

The assembly’s theme this year is “Restoring Trust, Managing Transformation: A United Nations that Delivers for All.” According to information received from the UN, leaders from 81 countries and heads of government from 50 countries, including Nepal, are expected to attend.

For Shah, the appearance will also be an opportunity to present the priorities of a government formed after last year’s youth-led protests, subsequent elections and a change in Nepal’s political landscape. Officials said the government would seek greater international cooperation and goodwill while outlining its domestic priorities.

Foreign minister Shishir Khanal will take part in ministerial meetings involving least developed countries, landlocked developing countries, the Non-Aligned Movement and the G77 and China. He is also expected to address UN meetings and side events and hold talks with counterparts from neighbouring and other countries, as well as senior UN officials.

The Nepali delegation will include Khanal, Shah’s chief adviser Kumar Byanjankar and foreign secretary Amrit Bahadur Rai, along with other senior officials.