Swedish climate activist Greta Thunberg says target dates for things like phasing out coal are not enough to save the climate - referring to one of Germany's landmark climate policies.

"We can't just talk about dates, a date for the phase-out of fossil fuels, a date for coal and so on. We have to talk in CO2, we have to talk in carbon budgets," she said in an interview with dpa.

"Because if we continue like now, then we have used up our CO2 budget before those dates that we announced," she continued. "It’s about thinking holistically."

Germany's new coalition government, led by Social Democrat Chancellor Olaf Scholz and propped up largely by the Greens, has vowed to bring forward the country's target date for shutting down the coal industry to 2030.

The plan is to pivot towards other sources of power, such as renewable energies and gas-fired power plants, which are being newly constructed.

When Germany's coal commission first set the target date in 2019, it was less ambitious at 2038. At the time, Thunberg called this "absurd."

dpa