This week, China took charge of hosting a major UN environmental conference for the first time, at the opening of Cop15 in Kunming. The world’s biggest greenhouse gas emitter and largest consumer of natural resources might seem a strange choice to host talks to stop the destruction of ecosystems and mass extinctions of wildlife, but the conference marks a tipping point in China’s development and an international debut for “ecological civilisation”, a little-known phrase outside its borders with big implications for the planet.

Amid uncertainty around whether President Xi Jinping will attend critical climate talks at Cop26 in Glasgow, the environmental slogan is at the heart of a potential misunderstanding between China and the west. Some commentators have been quick to suggest that Xi’s reported absence is proof that China has reverted to type, an example of the world leaders that “talk but don’t do” who have so irritated the Queen. But others point out that Xi, who has not left China since last year – he did not attend the UN general assembly in New York – and did not even travel to Kunming for the Cop15 summit that China was hosting this week, has been clear about his guiding principles on the environment.

“We shall take the development of an ecological civilisation as our guide to coordinate the relationship between man and nature,” Xi said in his keynote speech at the largely ceremonial opening of Cop15 in the southern province of Yunnan on Tuesday, where he announced a $233m (GBP170m) fund to protect biodiversity in developing countries. Governments are expected to reach a Paris-style UN agreement for nature during phase two of the summit next year by agreeing targets on reducing pollution, halting the spread of invasive species and increasing protected areas.

Xi emphasised the importance of living within planetary boundaries and building a green, low-carbon circular economy while solving problems created by industrialisation. Russia’s president, Vladimir Putin, also alluded to an ecological civilisation in his remarks to delegates. Prince Charles has hinted at it too, paying tribute to the “intimate understanding of nature” that has underpinned Chinese civilisation for thousands of years.

But what does ecological civilisation mean for China and the world? Superficially, it is the slogan for Chinese efforts to embrace environmental sustainability and move on from four decades of rapid economic growth that have come at great cost to nature, say experts. Beijing’s 2060 carbon-neutrality target, commitment to reach peak emissions by 2030 and decision to end financing for coal-fired power stations overseas are part of it, they add, but it also covers traditional medicine, the wildlife trade, hydropower dams and farming methods. Ecological civilisation is an axiom of “Xi Jinping Thought”, the Chinese president’s political ideology, now enshrined alongside Mao Zedong Thought and Deng Xiaoping Theory in the Chinese Communist party’s constitution.

“It started from 2017 when Xi Jinping inserted ecological civilisation into the party charter,” says Dr Yu Jie, of the London-based thinktank Chatham House. “It shows the huge significance of a policy revolving around environmental protection. Sustainable development is one of the key policy areas he is focusing on in his term. In the past few years, ecological civilisation has mostly been about words but very little deeds on the international stage. But I think the announcement from China about abolishing funding for coal-fired plants [abroad] is part of a change that is beginning to emerge.”

The opening of the repeatedly delayed Cop15 has presented China with an opportunity to bring ecological civilisation to the world stage. Unlike the UN climate talks, the US is not a party to the convention on biological diversity and China can more easily set the agenda. A declaration backed by more than 100 environment ministers this week has Ecological Civilisation: Building a Shared Future for All Life on Earth emblazoned at the top, a sign that Beijing wants to make its mark on biodiversity and climate talks.

“Many western policy analysts believe that perhaps climate diplomacy will be one of the elements where the US and China could work together. But actually, I don’t think so,” Yu cautions. “China will play a much bigger role in international environmental governance. We will see a much stronger push from Beijing for their environmental agenda to be adopted by the rest of the world.”

In China, ecological civilisation is marked by phrases with awkward English translations such as “green mountains are gold mountains and silver mountains”, commonly cited by Xi, which is meant to highlight the importance of a healthy environment to economic development. In the past few years another phrase, “building a beautiful China”, also popped up in Chinese state media, suggesting a top-level push in a similar direction.

Since Xi first used the phrase, a flurry of documents have been issued by central government, and reforms have been introduced. On Tuesday, Beijing announced it would establish China’s first national parks. State media say that the protected land area covers 89,000 sq miles (230,000 sq km), and nearly 30% of the main terrestrial wildlife species identified in China.

Phrases that feature ecological civilisation are everywhere now in Chinese media, says Ma Jun, a Beijing-based environmental campaigner and a former investigative journalist. Ma’s writing on pollution helped spark an environmental awakening in China in the early 2000s. His book, China’s Water Crisis – published in China in 1999 and in the west in 2004 – detailed the suffering of communities caused by pollution, which had largely been accepted as the price of economic development.

He said: “Chinese people are getting increasingly more affluent and they want a safe and sound environment. We are entering a new phase in human development. For the Industrial Revolution, man gained all this power to conquer and transform nature. But this new civilisation means that we need to try to live in harmony with nature. Mountains, rivers, forests, farmland, lakes, wetlands and grasslands: they are all part of a community. For an ecological civilisation, we must try to tackle the pollution of air, water and soil.”

As China grows richer, its citizens expect the environment they live in to be protected. It is also rewriting the social contract between the ruler and the ruled. Reports of water contamination and air pollution anger citizens, who then turn to social media to complain.

But despite the prominence of the phrase in China, some suggest that ecological civilisation is a triumph of style over substance when it comes to the environment.

Experts say that the decisions China makes in the next decade will define the success of international agreements on the climate and nature. But amid a growing energy crisis, China coal and natural gas imports have surged. Nor, so far, has Beijing joined the growing movement of countries pledging to protect 30% of land and sea by 2030 (the “30×30” initiative) led by France, Costa Rica and the UK, which recently added India to its ranks.

It is a dilemma for China’s policymakers. But whatever the final definition of ecological civilisation, Xi has made it the core of Beijing’s action on the environment.

“Ecological civilisation represents the development trend of human civilisation,” he said, as he concluded his speech on Tuesday. “Let us join hands and follow the philosophy of ecological civilisation and shoulder our responsibility for future generations.”

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