The author and presenter, who fronted the show between 1999 and 2009, took to Twitter, where she retweeted a post from The Sun columnist Dan Wootton about the change.
Dan wrote: "What appalling treatment of Eamonn Holmes and Ruth Langsford by This Morning and ITV.
"They’ve been absolute loyal rocks to that show through turmoil - and are beloved behind-the-scenes. Sad to see."
When she retweeted his comment, Fern added the words "Oh no?"
The kind-hearted broadcaster seemed sad for the long-time couple, who have fronted the show on Fridays and during holidays for the last 14 years.
WATCH: Fern Britton makes rare comment about her daughters
Her followers were equally surprised, with one writing the heartfelt response: "Is this fake news!? Oh, this is not right. Eamonn and Ruth are fab, I really feel for them. Another stupid decision this year!"
Another agreed, adding: "Big mistake. Love Ruth and Eamonn. Let’s hope another channel offers them their own morning show…"
The news comes amid reports that Alison Hammond and Dermot O'Leary are being lined up to replace the pair, with Ruth and Eamonn continuing the present This Morning during the summer holiday, when Phillip Schofield and Holly Willoughby traditionally take their annual six-week break.
Ruth and Eamonn are viewer favourites
Another of Fern's fans reacted to the news by suggesting: "Alison and Dermot will be a lovely change on a Friday, but it would be nice to give Eamonn & Ruth a day too."
The Mirror reported the shake-up on Saturday and according to the paper, the decision was made as it's "time for a change".
The article went on to say that everyone feels for the couple, who are well-liked on the team, but "tough decisions" had to be made.
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