The world is on a "highway to climate hell", United Nations Secretary-General Antonio Guterres told delegates during the opening ceremony of the COP27 World Leaders Summit in Egypt on Monday.

"We are in the fight of our lives. And we are losing," Guterres said. "Greenhouse gas emissions keep growing. Global temperatures keep rising. And our planet is fast approaching tipping points that will make climate chaos irreversible."

Guterres called for a "historic pact "between rich countries and developing nations to fund the phasing out of fossil fuels and accelerate the green transition.

"The two largest economies — the United States and China — have a particular responsibility to join efforts to make this pact a reality," he said.

China will beef up actions to synergize the reduction of both pollution and carbon emissions as it forges ahead with its climate targets, said Zhao Yingmin, head of the Chinese delegation to the COP27 United Nations climate change conference, on Sunday.

Zhao, who is also vice-minister of ecology and environment, made the remark at a seminar held on the sidelines of COP27 in Sharm el-Sheikh.

The vice-minister noted China has achieved significant success in the past in tackling climate change and China aims to peak carbon dioxide emissions before 2030 and realize carbon neutrality before 2060.

Thanks to the persistent efforts to enhance energy conservation and reduce carbon emissions in key industries such as steel, electrolytic aluminum and cement, he said, the country's energy consumption and carbon dioxide emissions per unit of GDP dropped in 2021 by 2.7 percent and 3.8 percent, respectively.

In the past 10 years, China has managed to afforest 64 million hectares of land. To date, the total area of man-made forest in China has reached 87.6 million hectares. "China has recorded the fastest growth in its forest resources in the world," he said.

As of the end of last year, the proportion of coal in China's energy consumption mix fell to 56 percent, compared with 72.4 percent in 2005, Zhao said. The country's total installed capacity for renewable energy generation has risen to 1.1 billion kilowatts, with capacity of hydropower, wind, solar and biomass ranking top in the world.

The US and China inked a milestone joint climate agreement at the COP26 conference in Glasgow last November. At that gathering, China's climate envoy Xie Zhenhua lamented rich nations' failure to meet climate funding targets for poor regions, and the diplomat reiterated this critique on Sunday in Sharm el-Sheikh, where this year's conference will run until Nov 18. "I hope the conference this time will meet the demands of developing countries as much as possible as it is held in Egypt, a developing nation," Xie said.