In a discussion on Politics Live about a dinner the prime minister hosted for Tory MPs yesterday, the Conservative MP for Aylesbury confirmed Johnson made the comments but rejected critics who said he got "the tone badly wrong".
"He made a joke. It was a lighthearted joke," she said.
"Appallingly bad taste," SNP MP John Nicolson replied and said the prime minister had got "the tone badly wrong" after appearing to question whether Wallis' revelation was triggered by Johnson's joke.
"Not correct at all," Leadsom retorted, "the prime minister right from the despatch box only last week was talking about how absolutely vital it is that all trans people are treated with the maximum respect and kindness and generosity."
In parliament last week, Johnson said the “basic facts of biology” are “overwhelmingly important” after being asked about trans rights at PMQs.
He added that when people are keen to “make a transition in their lives” they must be “treated with the maximum possible generosity and respect”.
"We have systems in this country that allow that and have done for a long time, and we should be very proud of it,” he said.
Leadsom continued: "Our colleague has been hugely supported by Conservatives and we all gather round one of our own who has made a very very brave statement in appalling circumstances and I don't think it is right or fair that you should somehow suggest that the prime minister's lighthearted joke led to such a very very serious statement."
Andrea Leadsom says joke made by Boris Johnson at Conservative dinner last night referencing "those who had been assigned male and female at birth" was "lighthearted"\n\n"Appallingly bad taste," says SNP MP John Nicolson\n#PoliticsLive https://bbc.in/3JRUYjL\u00a0pic.twitter.com/5vbhEfa0AH
Let's remember the joke in question because - yes - the sun has risen on a new day and the news once again is dominated by arguing over comments Johnson has made, because this is the prime minister we have.
"Good evening ladies and gentleman, or as Keir Starmer would put it, people who are assigned female or male at birth,” he had quipped, according to Politico, referring to the Labour leader's refusal to answer whether a woman can have a penis in an interview with LBC earlier this week.
The morning after he made the joke Wallis posted a statement on Twitter about his gender dysphoria. It read:
"I’m trans. Or to be more accurate, I want to be. I’ve been diagnosed with gender dysphoria and I’ve felt this way since I was a very young child. I had no intention of ever sharing this with you. I always imagined I would leave politics well before I ever said this out loud.
"I have never lived my truth and I’m not sure how. Perhaps it starts with telling everyone."
In a new statement, Wallis said: "I am overwhelmed by the kindness and support I have received in the last few hours. I am proud to be completely open and honest about the struggles I have had, and continue to have, with my identity. However, I remain the same person I was yesterday. For the time being, I will continue to present as I always have and will use he/him/his pronouns."
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