Tempering expectations on a global climate deal in Paris this year, the U.N.'s top climate diplomat has warned against assuming the pact will "miraculously solve climate change."

As negotiators prepare for a new round of talks in Geneva next week, U.N. climate chief Christiana Figueres said Thursday the role of the deal is to chart the course for countermeasures that can be scaled up over time.

Countries are supposed to announce well before the Paris summit in December how they plan to contribute to reducing global emissions of greenhouse gases. The European Union, U.S., China and Norway have already done so.

Figueres said it's already clear the combined pledges won't match what scientists say is required to avoid dangerous warming, meaning deeper cuts have to occur in the future.