Anne, 62, and the rest of the panel – Christine Bleakley, Stacey Solomon and Nadia Sawalha – couldn't help but bring up Piers' good friend, President Donald Trump.
As she quizzed Piers, 51, about Trump's ban on muslims, the Good Morning Britain host snapped at Anne as he struggled to get a word in.
"I heard your question, let me answer!" he said, speaking over her.
"The reason they're going after Trump is because he's a republican," Piers continued.
"We can all keep having this massive hissy fit or we can be more pragmatic. Everyone keeps screaming at me to not like him. It's not going to work, he's my friend."
Loose Women: Piers Morgan and Anne Diamond disagreed over Donald Trump today
Loose Women: Piers Morgan told Anne Diamond to let him him answer
GMB: Piers Morgan & Susanna Reid take on politicians
Tue, January 24, 2017
Good Morning Britain hosts Piers Morgan and Susanna Reid talk politics with Theresa May, Nigel Farage, Donald Trump and more.
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Good Morning Britain talks politics with Theresa May, Donald Trump, Nigel Farage, & more
I heard your question, let me answer!
When asked to explain his view on the Women's Marches which took place around the world earlier this month, Piers stood by his original sentiment.
"I didn't get the point of it, it didn't seem very focused to me. When it comes to women's rights, I'm absolutely a campaigner for that, I was brought up around very strong women."
Piers then revealed that none of the women in his life attended a march.
"None of them could actually see the focal point about what the march was about," he explained.
"I think marches and protests need to be very focused."
Piers' appearance on Loose Women comes after he clashed with Shami Chakrabarti on the ITV breakfast show today.
The 47-year-old Labour politician suggested that the tone of Trump’s rhetoric felt like a return to the 1930s, which prompted Piers to hit back.
Shami said she opposed a state visit by President Trump to Britain, saying: "I’m not suggesting Mr Trump shouldn’t be able to come and have meetings with the Prime Minister and so on, I’m just suggesting that a red carpet and a state banquet and an audience with the Queen is something that shouldn’t be put lightly."
Piers then replied: "Just to push you on this because I did a bit of research also into the number of countries we’ve given state visits too, where they themselves have bans in place, preventing sections of the community from going to their countries.
"Notably Israel, Iran, Kuwait, Lebanon, Libya, Saudia Arabia, Syria, Yemen. Five of which are on Trump’s banned list. You’re not allowed to go there if you have Israel on your passport.
"A number of people we’ve given state visits to the UAE, Kuwait, Saudi having existing bans on Israelis coming to their country, now isn’t there a rank hypocrisy with people jumping up and down?"
Loose Women continues weekdays at 12.30pm on ITV.