The Paris Agreement on global warming is “irreversible and non-negotiable”, the European Union has said in a blunt warning to climate science denier Donald Trump.

The EU and 79 developing countries in Africa, the Pacific and Caribbean issued a statement in which they reaffirmed their commitment to the landmark deal and called for others to do the same.

The Trump administration is currently considering whether to withdraw from the agreement, which committed the world to keeping global warming to as close to 1.5 degrees Celsius as possible.

The US President has laughably described climate change as a hoax perpetrated by China, a suggestion one of his advisers later described as an “exaggeration”.

Without specifically mentioning Mr Trump, Miguel Arias Cañete, the European Commissioner for climate action and energy, said: “Today more than ever, Europe stands by its long-term partners most vulnerable to climate change.

“We, developed and developing countries together, will defend the Paris Agreement.

“We are all in, and our joint commitment to this agreement today is as in Paris: irreversible and non-negotiable.”

And Patrick Gomes, Secretary-General of the African, Caribbean and Pacific Group of States (ACP), said: “The longstanding, ongoing cooperation between the ACP group and the EU shows we are serious about addressing the impacts of climate change.

“Implementing the Paris Agreement is not only about ensuring the very survival of the 79 ACP countries, but also about building sustainable, resilient and prosperous economies and societies worldwide.”

They made the call at a United Nation’s climate change conference taking place in Bonn, Germany, ahead of forthcoming meetings of the G7 and G20 groups of world leaders.

The EU announced it would provide 800 million euros (about £680m) of support to ACP countries with about half to be used to address climate change.

The Paris Agreement contained pledges and aspirations but work is still being done to develop actual action that this achieve the goals.

The Trump administration is believed to be split over whether to withdraw the US as a signatory to the Paris Agreement.

Some, like Defence Secretary James Mattis are believed to recognise the dangers posed by climate change – something that has been taken seriously by the Pentagon for years, given the threats to global security.

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Others are thought to be in favour of staying in so that the US simply has a “seat at the table” during future talks and to avoid paying a diplomatic cost of withdrawing from a major international agreement.