A global council with enforcement powers is the only way to save the planet, according to Rome Mayor Walter Veltroni.
Speaking at a science fair devoted to climate change, the mayor called for an ''environmental version'' of the United Nations Security Council.
''An environmental security council with binding powers is needed, providing a forum in which governments can take global decisions,'' said Veltroni.
''We must give ourselves effective weapons in the fight against pollution, and instead of investing resources in missiles, spend the money on climate change.
''This is the only way we can win the only war really worth fighting,'' he added.
He stressed that a global approach was needed to tackle the problem effectively. Climate change could never be dismissed as a local issue, he said, as activity in one part of the world eventually affects everywhere else.
The mayor, who also heads the newly created centre-left Democratic Party, said action must be taken immediately or it would be ''too late''.
The head of the UN-backed Intergovernmental Panel on Climate Change (IPCC), Rajendra Pachauri, issued a similar warning.
He said the world had ''just seven years'' to reduce carbon dioxide emissions, blamed for global warming.
''The scientific evidence is clear: we are responsible for climate change,'' said Pachauri, who last month accepted the Nobel Peace prize on behalf of the IPCC along with co-recipient Al Gore.
''We have very little time left - we have to act today''.
The Science Festival, which runs in the capital until Sunday, is now in its third year.
This edition, entitled Global ConScience, has been organized to coincide with the UN International Year of the Planet Earth.
A series of meetings and debates have been lined up for the week, with guests including international scientists, philosophers, economists and political analysts.
While much of the focus will be on climate change, the event will also look at conflicts for food and water, food biotechnology and the threat to biological and cultural diversity.
