The 51-year-old ITV presenter got into a Twitter sparring match with the veteran broadcaster, 69, over the subject of fake news.
All this week Channel 4 are running a series of programmes looking at news in the post-truth era and in light of the now-infamous phrase "alternative facts".
However, Good Morning Britain star Piers was less than impressed with Jon and took to Twitter to hit out him, telling his 5.48 million followers: “So glad @jonsnowC4 has started a Fake News segment on @Channel4News. He's something of an expert at it.”
Along with the scathing tweet, Piers shared a news article from 2011 which revealed that Jon had been duped by false reports that Piers had been fired from his job at CNN and had tweeted about it.
Jon later deleted the post and apologised to Piers over the micro-blogging platform at the time, saying: “@piersmorgan Jon Snow suspended from Tweeting Piers Morgan henceforth.. dupe was duped alas.. apologies old chap.. sorry, I mean young man!”
But it appears that Piers has not forgotten the slight from 2011 and took aim at Jon yesterday.
Nevertheless, Jon hit back with an equally blistering tweet in which he said: ”And this from a man who got sacked from the Daily Mirror for making up news!”
Channel 4 News anchor Jon Snow
Good Morning Britain host Piers Morgan hit out at Jon Snow on Twitter
And this from a man who got sacked from the Daily Mirror for making up news!
Jon was making reference to Piers’ dismissal of the editor of the Mirror in 2004 after the newspaper published fake images of Iraqi prisoners of war being abused by British soldiers.
Following Piers’ firing, the Mirror published an apologetic front page with the headline: “SORRY.. WE WERE HOAXED.”
The digital editor of Channel 4 News Jon Laurence also came to his colleague’s defence today as he posted: “.@piersmorgan calls @jonsnowC4 an 'expert in fake news'. He should know. He was doing it before it was cool.”
He also shared a picture of The Mirror front page in which they said the images were not real and they had been duped.
Piers Morgan has been caught up in Twitter spats with many others
Piers Morgan's most famous Twitter spats
Thu, September 22, 2016
Good Morning Britain host, Piers Morgan's most outrageous quotes and Twitter spats.
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Piers Morgan's most outrageous quotes
Piers was having none of it and lashed out with another tweet: “More Fake News! I was sacked from the Mirror for exposing the truth about rogue QLR troops, as was later confirmed.”
The feud appeared to come to a close when Jon turned his attention to other news matters and Piers finished up by saying: “I like Jon but he made up fake news about me & had to apologise for it. Seems pertinent to remind him now.”
This is not the first time that Piers has got into social media sparring matches, previous stars he’s got embroiled with have included Chrissy Teigen, Madonna, Rihanna and Charlotte Church, among many others.
Channel 4’s week of Fake News programming continues with Britain’s Greatest Hoaxer tonight at 10pm.