Morgan posted a picture of his co-host to Twitter, showing off the short pink dress and questioning where the rest of it had gone.
He wrote: “Wardrobe department forgot the rest of Susanna's dress today.
“Complaints are NOT pouring in…”
Wardrobe department forgot the rest of Susanna’s dress today. Complaints are NOT pouring in... pic.twitter.com/n1VanoynnP— Piers Morgan (@piersmorgan) 16 May 2018
The broadcaster was soon inundated with replies from his followers, many complimenting Reid’s outfit and telling her to “ignore” Morgan’s comment.
One wrote: “Dear Susanna - please ignore pompous Piers - girl - you've got the legs to rock that dress…”
While another said: “Only compliments and rightly so because @susannareid100 is a sexy, gorgeous lady with I might add a cracking set of pins and a national treasure.”
“Please get Susanna to snap a photo of u flashing ur legs do we can all comment,” somebody else suggested.
Morgan also joked about the stunning outfit on air, saying that “Susanna declared summer early”.
Earlier this month, Morgan mocked Reid for a different frock as he compared her attire to “pyjamas” .
But Reid joked: “It’s a nightshirt. She’s put me in a nightshirt.”
Good Morning Britain airs weekdays from 6am on ITV.