This is The Guardian.

Today, the landmark report the UK government didn't want you to see.

Last October, I and other journalists got quite excited because we thought that we were going to be attending a great event at the Natural History Museum.

This is Fiona Harvey. She's Environment Editor at The Guardian.

And we'd be talking about biodiversity, because the Natural History Museum,

and looking at the risks and the crises that we're facing,

the joint crises of climate and biodiversity,

and looking ahead to what was going to happen at the COP,

the UN Climate Summit, just a few weeks later.

On the guest list were government ministers, ambassadors, eminent scientists, even the king.

We had been told that there was a major report being launched at this event.

And this report was going to come not just from where you'd

expect, from the government's environment department, but also from the Joint Intelligence Committee.

And they are the UK's spy chiefs, MI5, MI6, the intelligence agencies, and they were taking interest in the climate

and biodiversity and the threats that they posed to the UK's national security.

The day before the event, Fiona was told that she was no longer welcome. And it wasn't just her, but all the other

journalists on the list. At first we thought perhaps it was the palace who can be a bit sensitive

about such things. But when it transpired that this report, this key report was not coming

out after all, we realised there was something bigger of foot.

Fiona, well, she did what she does best. She began to dig around.

I went and tried to talk to as many contacts as I could to find out about the report,

what was in it, who'd written it, what the advice was to ministers and how it was going to be acted upon.

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