ITV has said it investigated “rumours” of a relationship between Phillip Schofield and a younger employee in 2020 - but both “repeatedly denied” it.
Schofield quit ITV on Friday after admitting he had had an affair with a younger male colleague at the network and had lied to cover it up.
The TV presenter said the relationship had been "unwise, but not illegal".
Some former ITV daytime figures said the revelations raised questions about how much the network's managers knew.
An ITV spokesperson said: "Further to our statement last night, ITV can confirm that when rumours of a relationship between Phillip Schofield and an employee of ITV first began to circulate in early 2020, ITV investigated.
"Both parties were questioned and both categorically and repeatedly denied the rumours as did Phillip's then agency YMU.
"In addition, ITV spoke to a number of people who worked on This Morning and were not provided with, and did not find, any evidence of a relationship beyond hearsay and rumour.
"Phillip's statement yesterday reveals that he lied to people at ITV, from senior management to fellow presenters, to YMU, to the media and to others over this relationship."
The statement follows comments made by former ITV daytime presenters including Eamonn Holmes and Dan Wootton that ITV bosses had questions to answer about how much oversight they had on one of their most high-profile presenters.
Schofield released a statement to the Daily Mail on Friday, confirming he had had an affair with a young male employee who worked at the channel.
He was still married to his wife Stephanie Lowe at the time of the affair. They separated in 2020, after he came out as gay.
The TV presenter said he was "so, very, very sorry" for being unfaithful to his wife, and for lying to his colleagues, agents, employers, friends, the media and the public about the relationship.
The 61-year-old's exit from the network means he will no longer present the British Soap Awards next month.
He will also not front a new prime-time series which ITV had said last week they were developing with him.
Schofield left his role at This Morning last week after reports of a rift with co-star Holly Willoughby.
But in his statement on Friday, Schofield said his departure from the show was unrelated to the affair with the colleague, who the BBC is not naming.
An earlier statement from ITV about the affair said: "Phillip made assurances to us which he now acknowledges were untrue and we feel badly let down."
Schofield's confirmation of the affair follows significant online speculation over several months about his personal relationships.
Talent agency YMU has also cut ties with the presenter following his announcement.
In a statement to the BBC, Schofield said: "It is with the most profound regret that after 35 years of being faultlessly managed by YMU I have agreed to step down from their representation with immediate effect."
