Comedian Seann Walsh said he 'deeply' regrets his kiss with his Strictly Come Dancing partner Katya Jones, but insisted he is not the person he is being portrayed as.
The pair have been at the centre of controversy after The Sun published pictures of them kissing on a night out, despite both being in relationships.
Earlier this week, Mr Walsh was publicly dumped by his Norwich-born girlfriend Rebecca Humphries.
He has now appeared on BBC's Strictly spin-off show It Takes Two with Mrs Jones to address the scrutiny.
Mr Walsh, 32, said: 'I think that, obviously I'm sorry for the hurt that I've caused.
'We were getting on well, we were having fun.
'We had a couple of drinks and made a huge mistake and I regret it deeply.'
The pair apologised in separate statements on social media before appearing on the show on Wednesday.
Mr Walsh's long-term partner said in a statement that he had called her 'psycho/nuts/mental' when she suspected something was going on.
He told It Takes Two host Zoe Ball: 'I think first of all I would rather not be having to address this publicly, but I feel like I have to.
'I made a mistake, which I'm very sorry for - sorry for the hurt that I've caused.
'You never think about the extent of the damage that you're going to do, in a moment of, you know the mistake that you've made.
'I'm not perfect, far from it. Our relationship wasn't perfect.
'That doesn't mean I wanted it to end the way it finally did, and I'm very sorry for that.'
He added: 'I feel it's also important for me to say that the people that know me the most, that love me, they know that I am not the person I'm being portrayed as.
'I'm still sorry for what I did, but it's very important for me to get that out there.'
Mrs Jones, 29, is married to fellow Strictly dancer Neil Jones and in the aftermath of the pictures being published she said they were 'very happy' and that the incident was not a reflection on their relationship.
She told Ball: 'Yes obviously I apologise, and I can't apologise enough to everyone who it hurt and involved.
'But, the main thing, me and Neil are absolutely fine and that's what matters to me the most right now and focusing on my job and doing it as professionally as I can.'
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