In a statement to the Daily Mail on Fridy evening, the ex-This Morning presenter, 61, admitted an “unwise but not illegal” relationship with the man while he was still married to his wife of 30 years.
He said: “I did have a consensual on-off relationship with a younger male colleague at This Morning.
“Contrary to speculation, whilst I met the man when he was a teenager and was asked to help him to get into television, it was only after he started to work on the show that it became more than just a friendship.
“That relationship was unwise, but not illegal.”
He said he had lied to ITV about the relationship with the ex-colleague and that he would be resigning from the broadcaster with immediate effect.
Schofield said he had never issued an injuction about the relationship and that the person was never moved on or sacked from This Morning because of it.
“I am painfully conscious that I have lied to my employers at ITV, to my colleagues and friends, to my agents, to the media and therefore the public and most importantly of all to my family,” he told the paper.
“I am so very, very sorry, as I am for having been unfaithful to my wife.
“I have therefore decided to step down from the British Soap Awards, my last public commitment, and am resigning from ITV with immediate effect expressing my immense gratitude to them for all the amazing opportunities that they have given me.
“I will reflect on my very bad judgement in both participating in the relationship and then lying about it.”
ITV confirmed they have accepted his resignation and that he will no longer be appearing on the channel.
A spokesperson said: “We are deeply disappointed by the admissions of deceit made tonight by Phillip Schofield.
“The relationships we have with those we work with are based on trust. Phillip made assurances to us which he now acknowledges were untrue and we feel badly let down.
“We accept his resignation from ITV and therefore can confirm that he will not be appearing on ITV as had previously been stated.”
His agent YMU group said it had parted ways with Schofield after it learned “important new information” about the media personality which contradicted what the star had previously told them.
His recent departure from This Morning came amid reports of a rift between Schofield and co-presenter Holly Willoughby.
In a statement on Thursday, CEO of YMU Group, Mary Bekhait, said: “Honesty and integrity are core values for YMU’s whole business, defining everything we do.
“Talent management is a relationship based entirely on trust.
“This week, we have learned important new information about our client Phillip Schofield. These facts contradicted what Phillip had previously told YMU, as well as the external advisors we had brought in to support him.
“As a result, on Thursday we agreed to part company with Phillip, with immediate effect.”
In a statement through a lawyer, 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.”
Schofield, who had co-presented This Morning with Willoughby since 2009, said last week he decided to leave the show because it had “become the story”.
He said in last week’s statement: “Throughout my career in TV – including the very difficult last few days – I have always done my best to be honourable and kind.
“I understand that ITV has decided the current situation can’t go on, and I want to do what I can to protect the show that I love.
“So I have agreed to step down from This Morning with immediate effect, in the hope that the show can move forward to a bright future.”
Schofield’s wife, Stephanie - who shares two children with Phillip - previously stood by him when he revealed in 2020 he was gay on ITV after 27 years of marriage.
At the time, his wife said: “We have had to face the most emotionally painful time in our 27 years of marriage.”
He started at This Morning in 2002 as a temporary presenter before becoming a permanent fixture at the show.
Fern Britton, his original co-host, quit the programme in 2009, with Britton replaced with Willoughby.