Boris Johnson has been confronted by a BBC interviewer over plans for a new British coal mine - while at a global climate summit.
The Prime Minister was quizzed over a firm's plans to mine coking coal for steel in Cumbria, that is subject to a planning row.
For the first time he confirmed he does not want to see the plant built - but said it was up to planning authorities, not him.
It comes after pledges by G20 leaders to end global reliance on coal were watered down at yesterday's summit in Rome.
Mr Johnson had vowed to pressure leaders over "coal, cars, cash and trees" ahead of today's COP26 climate summit in Glasgow.
But G20 leaders are thought to have removed a pledge to stop building new coal power plants in the 2030.
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Instead they pledged to end "international public finance" for overseas new coal power stations by the end of this year.
While Mr Johnson slammed the pledge as not good enough, he has faced scrutiny over the coal mine plans closer to home.
BBC climate editor Justin Rowlatt told the PM he was making global pledges "at the same time as not ruling out a new coal mine in Britain".
In an interview aired as the summit began, the journalist said: "A new coal mine in Britain! We started the industrial revolution, we should close the mines!"
When the Prime Minister stuttered over his answer the journalist added: "Why don't you just say we're not going to open [it].
"The Chinese are going to say we can't take this guy seriously!"
He suggested it was "weasely" not to answer the question.
Mr Johnson insisted: "When I was a kid, 80% of our power came from coal. When I was mayor of London it was 40%. It's now 1%."
When pressed, he added: "I'm not in favour of more coal, let's be absolutely clear. But it is not a decision for me, it is a decision for the planning authorities."
West Cumbria Mining wants to mine the coal for steelmaking, rather than power generation, at a former chemical works in Whitehaven. A planning inspector has held a public inquiry and will reach a final decision around the end of the year.
COP26 President Alok Sharma today urged polluting countries not to "give up" on phasing out coal.
He told i News: "If we don’t consign coal power to history the whole world will regret it, quite frankly."
Mr Johnson meanwhile dodged saying whether he would eat less red meat, instead saying he was trying to eat less of everything.
And he joked he had "abolished commuting" by living in the flat above 11 Downing Street.
Friends of the Earth climate campaigner, Tony Bosworth, said: “Actions speak louder than words. If Boris Johnson is not in favour of more coal, why did it take his government so long to ‘call in’ planning permission for a new coal mine in Cumbria?
“The prime minister’s push for an early end to coal must cover industrial uses too, not just power generation. The climate doesn’t differentiate between the two.”
