UN Secretary-General Antonio Guterres on Wednesday called for a fight against disinformation related to climate change, following US President Donald Trump's description of it as "the greatest scam in history."

Ahead of next month's COP30 summit, Guterres argued that without "clear-eyed" climate science and data, the world would never have understood the emergence of the "dangerous and existential threat of climate change."

"We must fight disinformation and misinformation, online harassment, and greenwashing," Guterres stated at the World Meteorological Organization (WMO), the UN agency dedicated to weather and climate.

"Scientists and researchers should never be afraid to speak the truth," he added at the agency's headquarters in Geneva.

In September, Trump told the UN General Assembly that climate change was "the greatest scam ever perpetrated on the world" and that the concept of a carbon footprint was "a hoax invented by people with bad intentions."

"Global warming is pushing our planet to the brink," Guterres said on Wednesday.

"Each of the last ten years has been the hottest on record. Ocean heat is breaking records and destroying ecosystems. No country is safe from fires, floods, storms, and heatwaves."

"As always, the poorest and most vulnerable countries are paying the highest price, particularly developing small island states and the least developed countries," he continued.

The COP30 summit will be held in the Brazilian city of Belém, in the Amazon, from November 10th to 21st.

The UN Secretary-General stated that countries needed robust national climate action plans in time for the summit and urged nations to address the problem of climate disasters at their source.