Given the UK is hosting the COP26 summit next month, the British government was hoping the Royal Family might prove to be a valuable asset.
Ministers were secretly hoping that the respect many world leaders have for the Queen, and for Prince Charles, would translate into action – and would encourage countries to sign up to the dramatic carbon reductions needed in order to limit global temperature rises to 1.5°C.
Just this week, Prince Charles addressed delegates attending a conference in China – the world’s biggest polluter – and urged them to “properly price carbon”, a polite way of saying polluters should pay more.
What the British government would not have expected was the Queen referring to some of the world’s leaders as “irritating”.
The Queen was a long way from the microphones when she made her remarks during a conversation inside the Welsh Parliament.
It’s possible her words will force a meeting of minds ahead of the UN summit.
It’s possible those countries which currently rely on mining, exporting or burning coal will feel suitably chastised by the 95-year-old Monarch.
Leaders like Boris Johnson and the US climate envoy John Kerry, who are pushing for the 1.5°C target, might privately agree with the Queen.
Others, however, night conclude, she’s stepping into the political domain when convention dictates that Royals must not.
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It is rare to overhear the Queen making unguarded comments, but she has been caught in a “hot mic” moment involving the Chinese before.
At a Buckingham Palace garden party in 2016 to celebrate her 90th birthday, she was overheard referring to Chinese officials as “very rude” in the way they behaved when organising the state visit of President Xi Jingping.
Now the Queen has made it perfectly clear that she is not amused by the lack of commitment by some world leaders to November’s climate summit.
We wait to see quite how those leaders will respond.