Notorious GMB: Piers Morgan on Donald Trump, Twitter rivals and serial killers

“Do you have that on good authority?” I probe.

He shoots me a very meaningful look indeed, before answering: “I think he does, on his presidential throne.” Morgan then bursts into hysterical laughter.

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The breakfast host received a lot of flack for what many called his “sycophantic” interviews with the US President, with critics accusing Morgan of being too soft on Trump because of their friendship. “People always say to me, ‘How can you admit to being a friend of Donald Trump?’” says Morgan, sipping on a coffee in the GMB dressing room in west London. “I went, ‘Imagine how he feels? He has to be a friend of me, it’s a two-way street.’”

Morgan secured the first international television interview with Donald Trump after he came into office, speaking to him at the World Economic Forum in Davos, Switzerland, in January. He interviewed him again on Air Force One in July. Where will the third interview take place? “Well, the White House, obviously. Just to really piss people off.”

Speaking of the viewer reaction to his Trump interviews, Morgan is indignant: “People get all wound up about it. They say, ‘If I interviewed Donald Trump I'd take a big club in there, I'd club him over the head.’ Of course, they'd get as far as the first question and if he didn't like it he'd just say, ‘Thanks very much’ and he'd be led off. You’ve got to play the long game with people like that.”

Morgan’s approach to interviewing mass murderers is not dissimilar, it turns out – it’s all about playing “a game of cat and mouse”.

His latest subject, in Serial Killer with Piers Morgan, is Bronx businessman Alex Henriquez, who was convicted of three murders in 1992. This case really took its toll on Morgan because the victims were two young girls and one young woman. “It's hard to hide revulsion,” he says. “I've got a young daughter and when you see the age, you know, one of these kids is ten, another is 14, and you see the devastation caused to so many lives by the deaths of these young people, and you obviously think about your own family and how you'd feel, and you feel sickened.

“After, I go home to the hotel, pour myself a large drink and have a long, long hot shower and just try and drain it out of you because you feel sickened, really. It's sickening. You're wallowing in the most appalling crime and misery.”

Before Henriquez, the last serial killer Morgan interrogated was Lorenzo Gilyard, who “strangled probably up to 30 people, killed them with his bare hands”. Asked whether he ever feels frightened sitting across from these criminals, Morgan says he is “a bit apprehensive” but “there are heavily armed guards off camera”.

“Sometimes they give you warnings,” he says. “They say, ‘Look Mr Morgan, if they make an attempt to attack you then you please must let us handle it, do not engage with the prisoner.’”

Looking as chuffed as Donald Trump when he met the Queen, Morgan reveals that while filming the new episode of Serial Killer an FBI man offered him a job. “He thought my technique was really good, so I was very happy about that,” he grins. “One of the best compliments I've ever had. He was like, ‘Join the FBI!’” It appears that Morgan is genuinely considering the career move: “Actually, I've always thought journalists would make really good detectives and lawyers, it's all the same kind of thing of basically trying to get to the truth, and a lot of people are lying to you.”

Serial killers aside, Morgan says his most frightening interviewee was the former President of Iran, Mahmoud Ahmadinejad, who he came face to face with in New York in 2012. “That was a very heavy scene, that interview,” he recalls. “There were about 30 henchmen in the room, they removed all the baubles off the cupboards because they said they were too gaudy for the Iranian audience. The air-con had to be turned off in case people were poisoning us. It was all very heavy duty and a heavy, serious interview and that was quite intimidating, that whole atmosphere.

“When people are turning off air conditioning because they think they might be poisoned, you think, ‘Okay, this is serious stuff.’ The President of Iran in New York, I got the only interview. So that was probably the most apprehensive I've felt as an interviewer. Like, what am I involved in here?”

Changing the tone, he says his former America’s Got Talent co-judge Sharon Osbourne can be “equally dangerous” – “She's like one of my little dogs, you know. One false move and she'll bite you…” he laughs. “I've got a lot of sympathy for Ozzy.”

Morgan, who wakes up at 4:50am every morning to present GMB, only has nice things to say about his current colleagues at ITV, confessing he “loves” his famously tempestuous relationship with his long-suffering co-host Susanna Reid, and describing This Morning’s Holly Willoughby as the “perfect choice” to replace Ant McPartlin on I’m a Celebrity.

Although he would probably never admit as much, Morgan clearly has a similar affection for his long, long list of Twitter rivals. He happily gives me his verdict on the key players.

“As Lineker was as a footballer, he's a good finisher. He's obviously chief virtue signaller of Twitter, you know, he's St Gary.” Morgan reckons Lineker waits for him to tweet at him, observes the responses and looks for the best way to “jab me back and then nicks it and uses it”. “He's the ultimate poacher, like he was as a footballer. He used to goal hang at the six-yard box and just wait for a good pass. That's what he does,” he smiles.

Alan Sugar, meanwhile, just “gets angry and can't spell so I can always have him on that” and Dan Walker “is just another one with the old halo on his head and likes to be all saintly”. He adds that “Trump's always good fun to engage with because he tweets like I do. If you whack him, he whacks you back. It's extraordinary that Trump is 72 years old and is the best exponent of Twitter in the world.”

Morgan is well-known for hounding people on Twitter, whether in jest or not, but there is one tweet that he regrets sending. It was one posted in 2016 attacking Lady Gaga for saying she has PTSD after she was raped as a teenager. He now accepts that he may have been “a little too all-encompassingly judgemental”.

• Piers Morgan reveals the one tweet he regrets – attacking Lady Gaga for claiming she has PTSD

Every day, another unsuspecting figure falls prey to Morgan’s wrath – and on the day we meet it’s David Beckham and American plus-size model Tess Holliday. He finds the Beckhams “irritating as a brand”, he tells me, and “ridiculously hypocritical” for posing with their children on the cover of Vogue while “bleating on about privacy”. Holliday, meanwhile, was on the cover of Cosmopolitan and in a highly-publicised feud, Morgan accused the magazine of celebrating obesity. “There's nothing body positive about being 300lb as a mum of two, when you're 5ft 3, it's clearly morbidly obese and dangerous,” he argues.

His fiery rows with celebrities and public figures are a huge draw for GMB's audience, but can Morgan ever see himself leaving the breakfast show? “Oh, I'll be fired at some stage,” he laughs. “[Head of ITV] Kevin Lygo at the Edinburgh TV festival actually described me as ‘horrendous’. He's my boss. I think what he meant to say was ‘horrendously expensive’… I love Kevin. And actually I like having a boss who can crack jokes like that. I think they were jokes.”

On a more serious note, Morgan says he loves the “freedom I get” on GMB and that he’ll “do it as long as I'm enjoying it.

"The trick is to leave just the moment before everyone is screaming at you to go.”

Serial Killer with Piers Morgan airs on Thursday 13th September at 9pm on ITV