Dhaka, May 6 -- A hard-hitting report into the impact of humans on nature shows that nearly one million species risk becoming extinct within decades, while current efforts to conserve the earth's resources will likely fail without radical action, UN biodiversity experts said on Monday.

Speaking in Paris at the launch of the Global Assessment study - the first such report since 2005 - UNESCO Director-General Audrey Azoulay said its findings put the world "on notice".

"Following the adoption of this historic report, no one will be able to claim that they did not know," the head of the United Nations Educational, Scientific and Cultural Organization said.

"We can no longer continue to destroy the diversity of life. This is our responsibil...