Humans have "possibly" impacted the climate, but only "modestly", Reform UK's deputy leader Richard Tice MP has told Sky News.
The position is a long way from the scientific consensus that humans have dramatically disrupted the climate.
But it marks a shift in comparison with earlier in the year, when he told Sky News man-made climate change is "garbage".
Asked if humans have impacted the climate, he said: "Possibly, but if so, a very modest percentage."
It comes as exclusive polling for Sky News finds belief in and concern about man-made climate change remain high, despite scepticism from elite political figures.
The Boston and Skegness MP also acknowledged the need to update infrastructure in Britain so that it can cope with a changing climate.
In an interview in London ahead of the COP30 climate summit, he said: "Climate change is real, right? Everything changes, you have to adapt to it, you have to maintain and update sea level defences."
Read more: Why is COP30 so controversial?
He said he has "sea level issues", in his constituency on the east coast, though would not specify whether they were rising.
Mr Tice maintained the sun and volcanoes were the "two main drivers" of climate change, and the climate has been changing for "millions of years, always will be".
While the climate does consistently change, what worries scientists is that it is currently doing so at its fastest rate in at least a million years, making it hard for the natural world to adapt.
'They've not got a clue'
Mr Tice would not be drawn on whether he accepted the climate was warming at an unprecedented rate.
"From the data that I've seen, from previous ice core data, I think the answer to that is questionable," he said.
He said "thousands of scientists" agreed with him, and cited a statistical analysis published by Statistics Norway, the country's statistics bureau, that concluded the impact of emissions from human activity "does not appear to be strong enough to cause systematic changes in the temperature fluctuations during the last 200 years".
However, 99.9% of climate-related studies agree climate change is mainly caused by humans, according to a 2021 survey of 88,125 peer-reviewed papers in the IOP Science journal.
Science and space body NASA says "human activity is the principal cause" of unprecedentedly fast warming, while 234 UN scientists (the IPCC) call it "unequivocal" that humans have caused "widespread and rapid changes" - in a report signed off by 195 governments.
Mr Tice said: "The IPCC accepts that sea level rise will continue for between 200 and 1,000 years. In other words, they've not got a clue what they're talking about."
(c) Sky News 2025: Reform deputy stands firm on climate change scepticism


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