A U.N. climate panel warned Monday that greenhouse gas emissions must reach a peak by 2025 and head downward from there for the world to achieve a goal of limiting global temperature rise to 1.5 C above pre-industrial levels.

The Intergovernmental Panel on Climate Change, which provides governments with scientific information so they can come up with effective climate solutions, pointed out in the latest report by its working group that the current pace of emissions reduction is not enough.

The report updates the working group's contribution to a report released eight years ago.

The working group focuses on climate change mitigation by assessing means for reducing greenhouse gas emissions and removing such gases from the atmosphere.

Part of the report was released as the panel with 195 member states wrapped up an online general conference and working group conference that began March 21.

At last year's U.N. climate talks, called COP 26, governments reached an agreement on efforts to contain global temperature rise to 1.5 C compared with pre-industrial levels.

While the IPCC defines pre-industrial era as several centuries before large-scale industrial activities began around 1750, it uses average figures between 1850 and 1900 as pre-industrial level temperatures of the world because observation data worldwide are available for the period.

The panel had analyzed there would be a big difference in a magnitude of negative effects between limiting temperature rise to 2 C and to 1.5 C, and that in order to realize no or limited overshoot of 1.5 C, it will be necessary that global net anthropogenic CO2 emissions decline about 45 percent from 2010 levels by 2030 and reach net zero around 2050.

Moreover, it is believed that even if each country meets its reduction target, greenhouse gas emissions will still increase in 2030.

"The report calls on the whole world to further accelerate mitigation measures for climate change," Japanese Environment Minister Tsuyoshi Yamaguchi said in a statement.

Japan aims to achieve carbon neutrality by 2050 and reduce greenhouse gas emissions by 46 percent by fiscal 2030 compared with fiscal 2013 levels.

The Environment Ministry said in a preliminary report that greenhouse gas emissions in the country dropped in fiscal 2020, which ended in March 2021, for the seventh consecutive year.

But global emissions have been rising on economic growth in developing nations, among other factors. China, the world's largest emitter, has expected to reach its emissions peak by 2030.

The IPCC was created in 1988 by the World Meteorological Organization and the U.N. Environment Program.