The Tánaiste has said that allegations he had anything to gain from leaking a GP contract document "is false and without foundation".
He said he "refuted" the allegations and offered his apologies for what happened.
Leo Varadkar was addressing the Dáil this afternoon after admitting he sent the documents to the former President of a rival group to the IMO, the National Association of General Practitioners (NAGP), Dr Maitiú Ó Tuathail, between 11-16 April 2019.
The broad outline of an agreement was reached on April 5, with the IMO announcing a €210m deal.
Mr Ó Tuathail is a friend of Mr Varadkar, and campaigned for him when he ran for leader of Fine Gael.
"Rivalry between the IMO and NAGP was often bitter and held back process," said Mr Varadkar of the negotiations at the time.
"The government decided to go with IMO alone and opposition was critical of this at the time.
"We agreed to keep the NAGP involved, there was a role for the NAGP to be consulted and involved.
"I took an active and personal interest in the talks and kept in personal contact with a number of GPs who I felt were opinion leaders in this.
"This was my sole motivation all along, and the suggestion I had anything to gain personally is false and without foundation."
Mr Varadkar reiterated his stance that most of the contract was already public and had been published in press releases.
"The fact is an agreement had been reached and was not highly confidential or commercially sensitive," he added.
"For my part as Taoiseach I was keen the agreement should be well received by the GP community as a whole.
"At this time, I posted a document to Dr Maitiú Ó Tuathail on a confidential basis believing publication was imminent anyway.
"I wanted him to see there was nothing in the agreement worth opposing or agitating against.
"Providing them with information did not incur any gain for them over anyone else.
"In providing the copy of the agreement I was honoring a political commitment that the government had made.
"It has been alleged that something improper or criminal has happened, this is not the case.
"This is someone who I wanted to be supportive of the agreement.
"Ministers have a lot of numbers in their phones, the same goes for informal contacts in business leaders, there is nothing inappropriate of contact of this nature.
"Some people like to exaggerate their relationships of influence, claims of greater access than they have.
"Supporters claim to be closer to you than you are, most of us in this house are familiar with that.
"I accept posting the agreement was not best practice, it was an error, one I accept sole responsibility for.
"I do regret it, and sorry for the annoyance my actions have caused.
"I know I have made mistakes as Taoiseach, things I wanted to do and failed.
"Over my career, I've been guilty of errors of judgment or motives corrupt - not for a minute.
"My motivations are to serve my country."
There is an argument over how much of the document was in the public domain at that point and about whether or not the NAGP should have had access to the deal.
Mr Varadkar said that while he regretted the method in which the document was sent but he did not do anything illegal.
Rise TD Paul Murphy has asked the Standards In Public Office Commission to investigate the matter.
During sustained questioning from Sinn Féin's Pearse Doherty, Mr Varadkar said he had two different hard copies of the document.
Leo Varadkar got a copy of the document, read it, and then put it in the recycling bin, then ordered another one.
Pearse Doherty: "Why?"
Leo Varadkar: "I wanted to read it again."
Pearse Doherty: "Seriously?"
Leo Varadkar: "Yes."
The second document was the copy sent to Dr O Tuathail.
On the issue, Mr Doherty said: "This is old boys' club, favours for friends. I don't buy your explanation" and asks why it was sent to Dr O Tuathail's home if the NAGP office was across the road from Leinster House.
Mr Varadkar said he did not know where the office was.
Aodhán Ó Ríordáin said Mr Varadkar's judgment had been called into question.
"You say there was 'nothing inappropriate and supporters claim to be closer than they are', this is the entirety of the story.
"You as the Taoiseach with immense responsibility you had handed a document stamped 'confidential' and handed it to your friend the head of a rival organization."
Leo Varadkar confirmed he had contacted Dr Maitiú Ó Tuathail over the weekend and likewise the doctor contacted him. They spoke three times.
"Yes, we are friends, we're not closed friends. We would meet two or three times a year at a drinks reception or overlapping social circle.
"We're not best mates or anything more than that, that is not the case."
Referring a text that Dr Maitiú Ó Tuathail sent that stated Mr Varadkar "pulled strings for him", Mr Varadkar said it was "over-egging" his influence to the then-Taoiseach.
Social Democrat co-leader Catherine Murphy asked the Tanaiste if he accepts he broached confidentiality after reading from a message allegedly from the Tanaiste to Dr O Tuathail saying: "There may still be some changes made to it, don't take it as gospel".
Mr Varadkar says all agreements are subject to change or amendment.
He has denied he has ever leaked any other similar documents.
"This hasn't happened before and hasn't happened since," he said.
"I can say a circumstance like this never arose before."
"You're not able to tell everyone everything you do at any given moment of the day," Mr Varadkar said about his cabinet colleagues who were not aware he was sharing the contract.