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It is 1,014 days since Russia began its full-scale invasion of Ukraine.

On Friday, we got to hear the thoughts of a man who rarely airs his views publicly.

Richard Moore, head of the Secret Intelligence Service, MI6.

We have recently uncovered a staggeringly reckless campaign of Russian sabotage in Europe,

even as Putin and his acolytes resort to nuclear sabre-rattling,

to so fear about the consequences of aiding Ukraine and challenge Western resolve in so doing.

Such activity and rhetoric is dangerous and beyond irresponsible.

Now, Frank, you are the BBC's security correspondent.

You follow the words of people like Richard Moore very closely.

So your best place to explain to us what's he getting at here.

Essentially, he's referring to what's known as hybrid warfare or grey zone or subthreshold warfare.

What does that mean? It means where one country, one state, is damaging the interests of another

without necessarily reaching the threshold of an actual kinetic attack,

you know, without lobbing a missile or shooting lots of people or blowing something up in a big way,

but nevertheless causing a lot of damage to them.

And what is referring to here is things like cutting undersea cables,

there have been a number of

suspicious fires in what's believed to be incendiary devices that were loaded into the DHL cargo

system, in Leipzig, in Warsaw, and another one near Birmingham in the UK.

There's a lot of these activities going on.

Which are deniable, and I guess in some cases,

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