That's the grave verdict of a crucial United Nations (UN) assessment of how political pledges from 193 countries that signed the historic Paris Agreement stack up together.

It warns the world is on course for around 2.5C of warming, depending on whether promises are kept and targets are hit.

This shows progress since the landmark Paris climate accord was struck in 2015, when the world was on track for roughly 4C of warming.

But it is still far higher than the now widely accepted 1.5C limit that the world needs to stick to in order to avoid the worst impacts of climate change, including extreme flooding and drought, crop failures, disease spread and the loss of lives and livelihoods.

"To put it bluntly, countries' climate action plans as they currently stand simply aren't good enough," said executive secretary of UN Climate Change Simon Stiell, launching the report on Wednesday morning. "Humanity cannot accept that."

However, the annual synthesis of plans said that they are at least starting to bend the curve of global greenhouse gas emissions downward.

For the first time, the annual report has predicted that emissions will peak at 2030. Last year they were still set to continue rising after 2030.

But emissions are still not "demonstrating the rapid downward trend science says is necessary this decade", the report said, because the sooner they fall, the less global warming will be locked in long-term.

Read more: Everything you need to know about the United Nations climate talks in Egypt

Scientists agree emissions must fall 45% by 2030, in order to limit warming to 1.5C. Mr Steill said it would be impossible to lower global warming by the level needed unless rich countries fund action in poor countries too.

A promise to revisit and strengthen climate plans was hailed as one of the key successes from COP26 in Glasgow last year.

Mr Steill called it "disappointing" that only 24 have materialised in the last year, when many countries have been preoccupied with the war in Ukraine and ensuing energy and food crises.

But while the crisis has seen an increase in burning fossil fuels, it has also accelerated investments in renewable energy, he added.

Alok Sharma, MP and COP26 president, said the report shows that "although we have made some progress - and every fraction of a degree counts - much more is needed urgently."

The UK will in two weeks pass the baton to Egypt to take up the presidency for COP27, the UN climate summit hosting in November.

New climate plans that countries produced since COP26 are set to shave off about 6 gigatonnes from global emissions in 2030, roughly equivalent to the US's current annual emissions.

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