Image source, PA Media
Prime Minister Rishi Sunak will not attend the COP27 climate conference in Egypt next month, No 10 says.
Downing Street denied this represented a downgrading of climate change as a priority for the new prime minister.
Mr Sunak's predecessor Liz Truss had been due to attend the conference.
However, No 10 said the new PM would not be going "due to other pressing domestic commitments including preparations for the Autumn Budget".
A Downing Street spokeswoman said: "We remain committed to net zero and to leading international and domestic action to tackle climate change. The UK is forging ahead of many other countries on net zero.
"We will obviously continue to work closely with Egypt as the hosts of COP27 and to make sure that all countries are making progress on the historic commitments they made at the Glasgow climate pact."
COP27 will take place in Sharm el-Sheikh from 6 to 18 November - finishing the day before Chancellor Jeremy Hunt is due to set out the UK's tax and spending plans.
The annual UN climate summits are designed to help governments agree steps to limit global temperature rises. The UK hosted COP26 in Glasgow in 2021.
The news that Mr Sunak will not be attending comes as a UN report warns there is "no credible pathway" to keep the rise in global temperatures below the key threshold of 1.5C.
Scientists believe that going beyond 1.5C would see dangerous impacts for people all over the world.
The UN's emissions gap study also said that governments' carbon-cutting plans since last year's climate summit had been "woefully inadequate".