Chinese President Xi Jinping on Wednesday urged global cooperation to protect the Earth's biodiversity but stopped short of making a major environmental commitment at a UN summit notable for the absence of his US counterpart Donald Trump.
Some observers believed the Chinese leader may surprise world leaders as he did last week when announcing his country would go carbon neutral by 2060.
"The loss of biodiversity and the degradation of the ecosystem pose a major risk to human survival and development," Xi told the virtual meeting.
"Covid-19 reminds us of the interdependence between man and nature. It falls to all of us to act together and urgently to advance protection and development in parallel," he added.
Xi defended the "UN-centered international system" and the Paris climate accord, in what appeared to be an attack at the US, which is set to leave the landmark agreement.
Ahead of the summit, more than 60 heads of state and government promised to slash air pollution, eliminate ocean plastic and transition to more sustainable food systems by 2030.
Nations including Germany, France, Britain and Mexico promised to develop an "ambitious" plan ahead of next year's UN COP15 Biodiversity Conference that will be hosted by Xi in Kunming, China.
But other major countries including China, Brazil, Australia and Russia have so far not signed on.
The UN's periodic review of existing global conservation plans found this month that nations were set to miss all 20 targets they set themselves back in 2010 to halt nature loss.
The WWF's biennial Living Planet Index, released separately this month, showed that wild populations of animals, birds, fish and plants had plummeted nearly 70 percent since 1970.
As world leaders spoke at the summit, the environmental group Greenpeace held a protest near the UN building featuring melting sculptures of Donald Trump and Brazilian President Jair Bolsonaro.
The protest was aimed at highlighting the failures of both administrations to address the crises being discussed at the summit, and the fact that no one from the Trump administration was scheduled to address the event.
Bolsonaro did address the summit, where he lashed out, as he has done in the past, over international concerns at the rapid deforestation of the Amazon.
"I strongly reject international greed towards our coveted Amazon," he said, adding: "We shall defend it against actions and narratives that may prove harmful to our national interests."
An EU-Mercosur trade deal remains stalled over French concerns over the Amazon, which Brazil has said is motivated by protectionism.