Russia is committing grave acts of ecocide in Ukraine – and the results will harm the whole world | Andriy Yermak and Margot Wallström

By the war's end, it will be too late to prevent the worst consequences of these terrible crimes. Global leaders must act now

• Andriy Yermak is head of the Office of the President of Ukraine; Margot Wallstrom is a former foreign minister of Sweden

Robert Oppenheimer, the American physicist who led the team that developed the world's first nuclear weapons, quoted from ancient Hindu scriptures to illustrate his conflicting feelings about the forces his science unleashed: Now I am become Death, the destroyer of worlds," he said. In his later years, Oppenheimer longed for a future without nation states armed for war, and above all, a world without war".

Yet there's another kind of loss that Oppenheimer recognised only too clearly in his readings of the Bhagavad Gita, the ancient text he turned to after the bombings of Hiroshima and Nagasaki in 1945. Humans now possess the power to destroy the world they live in.

The people of Ukraine have grown cruelly familiar with war and death, inflicted on them by a nation state with vastly superior resources: they will never forget the human loss they have suffered in fighting to save their homeland. But Ukraine is also facing a destruction of habitat and nature on a scale that will reverberate far beyond its borders. While it is almost impossible to measure, the breadth and depth of this damage must be understood.

Russia has taken deliberate aim at Ukraine's environment: its rivers, forests and fields. Many of Ukraine's natural reserves - its animal and sea life, water and impressive biodiversity - have been terribly damaged or polluted. Toxins leak from its damaged industries and infrastructure. Global food security is at risk. The world cannot afford to ignore this growing environmental threat.

The overwhelming threat to Ukraine's environment was highlighted in June, with the extraordinary collapse of the huge Nova Kakhovka dam, which held back one of the biggest water reservoirs in Europe. This was no coincidental collapse: the dam was under Russian control when an explosion inside an internal passageway blew its concrete heart to pieces. This unleashed a catastrophic flood that wrecked over 40 towns and villages and one of the world's most valuable agricultural regions. Tonnes of oil were spilled into the Dnipro River. An uncountable number of landmines were strewn into the river and the Black Sea, leading to toxic leakage.