Eamonn Holmes and Ruth Langsford are being dropped from their weekly This Morning show - with Alison Hammond and Dermot O'Leary set to replace them.
The couple have presented the Friday morning slot on the ITV show together for the last 14 years.
Eamonn and Ruth are said to be "furious and upset" at the decision.
But despite being dropped from the weekly schedule, the couple will take over presenting the main show for six weeks over the summer holidays, when regular hosts Phillip Schofield and Holly Willoughby take a break, the Mirror reports.
Speaking about the decision to drop Eamonn and Ruth, a show insider said: “Eamonn is pretty furious and everyone feels for him and Ruth, they are well liked on the team, but sometimes tough decisions have to be made.”
Alison, 45, is already a firm favourite with This Morning viewers having been a roving reporter on the show, while former X Factor host Dermot, 47, has been at a loose end since the talent show came to an end last year.
The pair have previously appeared on This Morning as stand-in presenters together.
The insider said the duo had "a real warmth" and were "perfect" for the show.
Eamonn had previously said he feared being too “pale, stale and male” for gig following claims the show lacked diversity.
This Morning was recently criticised after broadcasting an entire show with only one non-white face.
ITV chief executive Carolyn McCall announced a Diversity Acceleration Plan in the summer.
The 60-year-old presenter also caused a media storm over his comments about a 5G conspiracy theory on the show.
Watchdog Ofcom said Eamonn's remarks, in which he said that mainstream media should not automatically slap down such claims, "risked undermining viewers' trust in advice from public authorities and scientific evidence".
Ruth, also 60, is expected to remain on lunchtime panel show Loose Women.
The changes are expected to come about in the New Year and it is understood that Alison and Dermot will be finalising contracts in the coming weeks.
