Following is a transcript of the video.

Luke Harding: My name is Luke Harding. I'm a journalist and a writer, and my new book is called "Collusion," and it's about Donald Trump and Russia.

I know about Russian espionage, I suffer through it myself to some degree. I spent four years in Moscow as The Guardian's bureau chief and I had goons from the FSB — basically the KGB — breaking into my apartment, following me around the icy streets of Moscow, sometimes in quite a kind of comic sort of a way.

You don't really grow accustomed to FSB surveillance, but what we discovered, basically you didn't have to be Sherlock Holmes to figure out that some strange people had been inside the flat because unlike in the movies, they left a series of blindingly obvious clues.

And I took advice from the British Embassy in Moscow from diplomats from London and they said, "Terribly sorry, old chap, but you're apartment is bugged." And I said, "Well, can you do something about it?" And they said, "No, we can't," and I discovered that they had video as well, including in the bedroom.

I think I understand kind of how these Russian intelligence people think. They are convinced that any American journalist, any British journalist, that we're all spies actually secretly working for the CIA or MI6 and that our goal is to undermine Russia by writing kind of propaganda.

Obviously, that's kind of crazy and wrong, but paradoxically that kind of gives us a degree of protection because there's one code for foreign spies, they can be harassed, they can be seduced, they can be exploited or surveilled, but ultimately you don't kill them. The people you kill are Russians who have betrayed the state and deserve the ultimate punishment.

The reason it's relevant is when you think about what happened in 2013 when Donald Trump famously visited the Ritz-Carlton Hotel for the Miss Universe beauty pageant. Did the Russians spy on him? Of course they did. It's what they do. For any kind of important guest, they would spy on him. So it's not really a question about whether they would have sought to kind of entrap him. It's a question of how he may or may not have behaved, and really only Donald Trump and Vladimir Putin know the answer to that.

EDITOR'S NOTE: This video was originally published on December 12, 2017. Natasha Bertrand and Lamar Salter contributed to this video.