SINGAPORE -- A United Nations biodiversity summit will be held in two parts, officials said late on Wednesday, confirming another delay to a much-needed global agreement to protect the planet's nature.

A virtual opening session will be held from Oct. 11 to 15 and in-person negotiations will be held from April 28 to May 8, 2022 in Kunming, China to finalise an agreement, the UN biodiversity body said in a statement.

The COP15, as the summit is known, has already been delayed twice due to the coronavirus pandemic and a third delay was all but certain because of the challenges posed by the lack of face-to-face meetings, Reuters reported last month.

"Decisive in-person meetings on a highly anticipated new UN agreement on biodiversity have been paused for a few more months by the coronavirus pandemic," the secretariat of the Convention on Biological Diversity said in a statement.

China's minister of ecology and environment, Huang Runqiu, said the host country would "fulfil the obligations of the host country, steadily advance the preparations, and make all efforts to host a landmark conference".

With growing calls for the world to protect nature in tandem with tackling climate change, countries are being urged at the conference to commit to put 30% of their land and sea territories under conservation by 2030.

The World Wide Fund for Nature (WWF) said the delays meant the "momentum to protect nature is at risk of stalling".

"Nature loss has not paused. It is essential that the extra time is used well," said Guido Broekhoven, head of policy, research and development at WWF International.