According to The Sun, the relationship between Phillip and his co-host Holly Willoughby has 'become strained in recent months', with a source alleging 'jealousy over her I'm A Celebrity Bafta success' is to blame.
It was even claimed that host Ruth Langsford has 'made an official complaint' against the 57-year-old presenter, adding that 'eight staff have spoken of a toxic atmosphere' on set.
But the allegations about Phillip have left ITV execs furious, with the telly network issuing a vehement denial.
In a statement, an ITV spokesperson said: "It’s deeply disappointing and unfair for Phillip to be the target of this sort of malicious gossip.
“Phillip is a much respected broadcaster and colleague and this is absolutely not a description of This Morning that we recognise.
“Holly and Phil are great friends both on and off screen and are popular among viewers and colleagues alike.”
Phillip is a much respected broadcaster and colleague and this is absolutely not a description of This Morning that we recognise.
Editor of This Morning, Martin Frizell, also told Entertainment Daily: "I spend hundreds of days a year in their company and what you see is what you get, a genuine friendship from a couple who are both spontaneously funny and professional.
"We have the smartest viewers watching telly and believe me they would be the first to notice any issues - they haven’t because there are none."
Phillip has presented This Morning since 2002, taking over from John Leslie after he was sacked from the show.
He initially co-hosted with Fern Britton, who was then replaced by Holly Willoughby when she quit in 2009.
This summer, Phil found himself at the centre of feud rumours with telly presenter and Britain's Got Talent judge Amanda Holden.
Amanda had allegedly claimed that 'overbearing' Phillip cost her the This Morning presenting job when co-host Holly went to Australia last year to stand in for Ant McPartlin on I'm A Celebrity .
Amanda then named Phillip as one of three things she wouldn't want to find in her house.Simon Cowell even got involved, by reportedly defending Amanda in a phone call, while ITV stood firmly in support of Phillip.
At the time, Phillip tweeted about the claims, saying that the tabloid newspapers "have got it in for me".
Phillip is yet to address the latest reports by The Sun on his social media accounts.
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