Canada said it would put in 200 million Canadian dollars ($147.20 million) and the United Kingdom contributed 10 million pounds ($12.60 million).

"We are off to a good start. We now call for further pledges from countries and from other sources so that the first projects under the new fund can be launched next year," said David Cooper, acting executive secretary of the U.N. Convention on Biological Diversity.

Campaign group Avaaz said the Global Biodiversity Framework Fund needed $200 million from at least three donors by December to be considered operational.

"The time for half-measures has passed," Avaaz director Oscar Soria said. "Surely donors can come up with the paltry $40 million" needed to get the fund up and running.

The meeting comes eight months after governments agreed the Kunming-Montreal Global Biodiversity Framework — what some have called the "Paris Agreement for Nature", invoking the landmark 2015 United Nations pact to tackle climate change.

One of the framework's 23 targets is to help mobilize public and private sector players to funnel $200 billion per year to conservation initiatives by 2030, with developed countries contributing at least $20 billion of this every year by 2025.

The fund launched on Thursday is managed within the Global Environment Facility (GEF) — a mechanism established under the U.N. Convention on Biological Diversity and the U.N. Framework Convention on Climate Change which has provided more than $23 billion to thousands of projects in the past 30 years.

The world's least developed countries and small island states will take priority and receive more than a third of the funds, with a target for as much as 20% to go to projects led by indigenous people, the GEF said in a statement.

($1 = 1.3587 Canadian dollars)

($1 = 0.7938 pounds)