Jon Gosselin says he really didn't want to do this.

The former reality star and father of eight says he never wanted to make this public... but now he has no choice.

So Jon is very sorry, but here he goes:

Gosselin says his 16-year old son is a liar.

The ex-TLC personality has been in the news of late for the worst possible reason: He's accused of assaulting his own child, Collin.

According to People Magazine, Jon and Collin got into a screaming match while the former was driving the latter around... and then the fight escalated to a horrible degree once they arrived home.

"Jon got out of the car enraged, put him in a headlock, punched him square in the nose, and when Collin fell to the ground, then he kicked him in the ribs," an insider told this publication a few days ago.

This same outlet, along with others, reported at the time that the Berks County Children & Youth Services in Pennsylvania had opened an investigation into Jon and the incident.

Through a rep, Gosselin all details alleged in the quote above.

But now Jon has come out and done the same himself.

"It's not true, I would never hit Collin, ever. I love him with all my heart," Jon told The Daily Mail on Friday, reluctantly explaining that Collin has mental health issues... and made a false report to police because he wasn't getting his way.

The Daily Mail claims that authorities did look into what allegedly transpired between father and son.

But ended the investigation after 24 hours.

Collin, for whatever it's worth, spent a few years living in a special needs facility until Jon got him out in late 2018 and won temporary custody of the teenager in court.

"I really didn't want to have to come out and talk about this for Collin's sake, but when Kate is in the media attacking me, calling me a child abuser, I have to defend myself," Jon also said, referencing hsi ex-wife.

"I love my son and I would never hurt him."

Jon added that his daughter, Hannah, who also lives with him, witnessed the argument between Jon and Collin and told the police that her father never struck her brother.

We have not confirmed this account ourselves.

Collin, though, went public with his allegation last week on Instagram.

Trashing his dad as a "liar," the teenager wrote:

"Yesterday he beat me up and thought nothing of it, he punched me in the face and gave me a swollen nose and I started bleeding. He then continued to kick me in the ribs after I was on the floor."

Collin quickly deleted the message, but here it is:

For her part, Kate Gosselin has spoken out loudly and strongly against her ex-husband, from whom she split in 2009 after eight kids and many years together as co-stars on jon and Kate Plus 8.

"I am horrified that this man is the father of my children," Kate told People this week. "I don't want my children to be associated with someone who loses his mind because his car got dented."

"I do not want this buried, swept under the rug or minimized," she continued.

"As a mother, I am not going to sit quietly and idly by while my child, any of my children, is assaulted by anyone, let alone their own father," Kate added to People.

"I am spotlighting this, and I will keep shouting about it, in the hopes that the authorities and the courts will finally do the right thing.

"Do not return my child to an abuser’s home.

"Jon needs to be charged with a crime. If this were your child, would you feel okay with having it swept under the rug?"

Jon, however, says none of this is warranted.

He tells The Daily Mail that Collin and Hannah got into a verbal fight on the way home from a dental appointment on September 2.

"It was just like sibling rivalry stuff, but when we got home things escalated into something different," Jon alleges.

"Collin got very upset and started acting out so I intervened. He started throwing stuff at my car, denting it and shouting f--k you."

Continued Jon in his own defense:

"I was angry and I confronted him and then he threatened to run away. We've had problems with Collin in the past running away and I was worried, he was upset so I restrained him.

"I didn't punch or kick him, I restrained him, which he obviously wasn't happy about. He's 16, he's a 16-year-old boy.

"I restrained him and then I backed away, because you never want to restrain your kids, it's the most heart-wrenching thing you ever have to do."

Gosselin says Collin then called the police.

"He was just pissed off because he didn't get his way. He was out of line and he's just making stuff up," Jon says.

"I get it, the police have to do their job," Jon said of how the issue got escalated to another department.

"The CYS came out and interviewed us and they also spoke to Collin's mother Kate and his other siblings and that was the end of it, the claims were unfounded."

As for why Collin wrote his disturbing, accusatory Instagram post?

Because Jon punished him by taking away his video game system for calling the cops and stirring up all this chaos.

Gosselin then trashed his ex-wife again.

"She hasn't seen Collin in five years and now she's going to try to come out as the caring mother when in fact the reason Collin is struggling with mental illness is because she abused him.

"He has PTSD because of her. So I'm not going to sit back and not defend myself or my family."