The pair, who were rumoured to be facing the chop earlier this month, will leave the ITV breakfast show within weeks after ratings failed to improve.
Chiles and Bleakley quit BBC's The One Show to join ITV on multi-million pound deals last year, but Daybreak ratings have fallen to figures as low as 350,000 in recent months.
A source told The Sun: "It's game over. ITV have tried everything to make the show work, but viewers are fed up with Adrian and Christine.
"The point of scrapping a well-liked brand like GMTV was to come up with something a lot better - but the opposite's been true."
Research has apparently concluded that viewers think Chiles is "grumpy" and see Bleakley as an "airhead".
An official announcement is expected on December 1 when new boss, former BBC Breakfast editor David Kermode, arrives. He is said to have taken the job on condition he could change the presenting lineup.
BBC Breakfast host Chris Hollins, former GMTV anchor Eamonn Holmes and Natasha Kaplinsky have been tipped as possible replacements, while Dan Lobb and Kate Garraway could be given bigger roles on Daybreak.
Bleakley was last night confirmed as the new host of Dancing On Ice after Holly Willoughby quit, apparently to present new BBC One singing competition The Voice.
> Christine Bleakley joins 'Guess the Star'