Marina Silva says contentious plan would be ‘ethical answer’ to climate crisis but does not commit Brazil to it

Brazil’s environment minister, Marina Silva, has urged all countries to have the courage to address the need for a fossil fuel phaseout, calling the drawing up of a roadmap for it an “ethical” response to the climate crisis.

She emphasised, however, that the process would be voluntary for those governments that wished to participate, and “self-determined”.

With temperatures breaching the Paris limit, experts say tackling the powerful gas could buy crucial time as the clean-energy shift stalls

• Cop30: click here for full Guardian coverage of the climate talks in Brazil

For two years, global temperatures have exceeded the 1.5C heating limit laid out in the Paris climate agreement. This overshooting will have “devastating consequences”, the UN secretary general, António Guterres, has warned.

The biggest worry for scientists is that further heating could trigger irreversible tipping points, such as the widespread drying out and dying off of the Amazon, or the melting of the Greenland ice sheet, beyond which climate breakdown could spiral out of control.