The report, culminating a two-year evaluation of the 2015 Paris climate agreement goals, distils thousands of submissions from experts, governments and campaigners.
"The Paris Agreement has driven near-universal climate action by setting goals and sending signals to the world regarding the urgency of responding to the climate crisis," it said.
"While action is proceeding, much more is needed now on all fronts."
More than 20 gigatonnes of further CO2 reductions were needed this decade - and global net zero by 2050 - in order to meet the goals, the U.N. assessment said.
Commitment was needed to phase out fossil fuels, set 2030 targets for renewable energy expansion, ensure the financial system funds climate action, and raise funds for adaptation and damage, he said.
Persons:
Tom Evans, Sultan Al Jaber, U.N, Antonio Guterres, David Stanway, Andrew Cawthorne
Organizations:
United Nations, United Arab Emirates, Reuters, Thomson
Locations:
Dubai, Paris, UAE, Singapore, Berlin