A flagship U.N. conference in China next spring, where governments are set to ink a new global pact to protect nature, could be thwarted by stricter travel restrictions imposed to contain the omicron coronavirus variant, environmentalists have warned.

About 195 countries are set to finalize an accord to safeguard plants, animals and ecosystems — similar to the Paris climate agreement — at the U.N. summit, known as COP15, scheduled for April 25 to May 8 in the city of Kunming.

But the rapid spread of the omicron variant around the world could throw a spanner in the works of the talks, which have already been postponed three times due to the difficulties of meeting face to face during the pandemic.