A key climate summit in Glasgow has been postponed until next year due to the coronavirus outbreak.
Around 30,000 politicians, environmental campaigners and journalists were due to attend COP26 on November 9.
A joint statement from the UK and the United Nations said “in light of the ongoing, worldwide effects of Covid-19, holding an ambitious, inclusive COP26 in November 2020 is no longer possible”.
UK energy secretary Alok Sharma, who is president-designate of COP26, said: “The world is currently facing an unprecedented global challenge and countries are rightly focusing their efforts on saving lives and fighting Covid-19. That is why we have decided to reschedule COP26.
“We will continue working tirelessly with our partners to deliver the ambition needed to tackle the climate crisis and I look forward to agreeing a new date for the conference.”
All nations were expected to put forward improved climate plans, five years on from the Paris agreement signed in December 2015 during COP21.
The summit was also planned as a key test for the North Sea oil and gas industry.
Oil and Gas Authority (OGA) chairman Tim Eggar challenged the sector to have work started on at least two major carbon capture and storage (CCS) by the time the event arrived.
UN Climate Change Executive Secretary Patricia Espinosa said: “Covid-19 is the most urgent threat facing humanity today, but we cannot forget that climate change is the biggest threat facing humanity over the long term.
“Soon, economies will restart. This is a chance for nations to recover better, to include the most vulnerable in those plans, and a chance to shape the 21st century economy in ways that are clean, green, healthy, just, safe and more resilient.”