The politician's aides sprung to his defence, explaining that the PM has been unwell ahead of his slot on the show. "He had food poisoning," an aide told the Sunday Times. "He was throwing up and had to change his suit because he got sick on his lapel."
WATCH: Boris Johnson doesn't know who Lorraine Kelly is
During the car crash interview, Boris left viewers amused after he failed to acknowledge who Lorraine Kelly is, asking Susanna "Who's Lorraine?" as Susanna handed over to the presenter for her show, which follows GMB in the morning schedule.
The PM's spokesperson was forced to defend him over this misunderstanding, commenting: "The Prime Minister wasn't fully across ITV's daytime line-up this morning, but you'll appreciate he has a number of issues to deal with," according to The Telegraph.
Lorraine and Susanna joked about the PM's lack of knowledge of daytime TV.
Boris Johnson was interview by Susanna Reid on GMB
On Wednesday morning, Susanna addressed Boris' comment, saying: "I'm looking forward to talking to Lorraine. I always say there is a Lorraine moment every morning but my goodness, yesterday's Lorraine moment was the one to end all Lorraine moments.
The 62-year-old replied: "It was very funny. Look, I don't expect people to know who I am, I really, really don't but I just thought that was - Do you not think, Susanna, he thought I was waiting in the wings to jump on him, to interview him because he looked frightened as if I was going to run in? I don't know."
Boris Johnson was unwell with food poisoning ahead of his GMB appearance
The GMB host responded: "I think he thought it was a joke to say that and I think he actually does [know who you are] because otherwise, he's the only person in the country who doesn't know who Lorraine Kelly is."
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