Boris Johnson attempted to explain to global media why he sat next to Sir David Attenborough without a mask at the COP26 climate conference in Glasgow.
Footage of the prime minister dozing off while not wearing a face-covering went viral this week, provoking outrage on social media.
COP26 has been billed as the last best chance to keep global temperature rises to no more than 1.5C, with Sir David critical of those who deny the climate crisis.
In conversation with BBC‘s science editor David Shukman, the naturalist and broadcaster said: “Every month that passes, it becomes more and more incontrovertible, the changes to the planet that we are responsible for that are having these devastating effects.”
He added: “If we don’t act now, it will be too late. We have to do it now.”
Wealthier western countries like the UK have a “moral responsibility” to help refugees displaced by climate change, the 95-year-old said.
“We caused it – our kind of industrialisation is one of the major factors in producing this change in climate. So we have a moral responsibility,” he told the BBC.
Johnson was challenged by a CNN anchor on why he chose not to wear a mask while sat next to Sir David.
His response has left many baffled:
Related: Elevenses: The New Denialism