"Can I say right from the start, this is never about me," he said in the press conference.
"It's about the person in the weather board, something that manifestly expressed what the National Party is about.
"It's about the person in many places, their right to transcend through the economic and social stratification of life."
Joyce said it has been an incredible privilege to serve as Deputy Prime Minister of Australia.
It went from bad to worse for Joyce this week. Yesterday, he denied claims of sexual harassment against him as "spurious and defamatory" as he faces fresh questions about an 11-day road trip he undertook in December.
The Deputy PM said there has been a litany a "litany of allegations" none of which have been sustained.
"Might I say right here, any person in any political party always says, the leaking, the backgrounding, all that, it will destroy not only our government, it will destroy any government," he said at the press conference today.
"Now, might I say, with the last allegation that was in the paper today, I have asked that be referred to the police. I've asked for the right of the person who's made the allegation and I've asked for my right of defence that be referred to the police," he said.
"But it's quite evident that you can't go to the Despatch Box with issues like that surrounding you."
Mr Joyce said the media attention was completely and utterly unwarranted.
He said he came to the decision to step down following the allegations made yesterday describing it as the straw that broke the camel's back.
"Obviously, it was confirmed by the allegations that I read in the paper. I just thought that has to be the straw that breaks the camel's back," he said.
Just hours ago, Nine News political reporter Lane Calcutt asked the Deputy PM if he was going anywhere following the sexual harassment complaint.
"Let's just do the presser," he said.
A spokesman for Joyce told The Daily Telegraph he had been made "indirectly aware" of the claim which he described as "spurious and defamatory".
"He said allegations of wrongdoing should be immediately referred to police so that the veracity of any claim could be properly tested," the spokesman said.
Joyce faced a formal leadership challenge with a possible showdown next Monday after a Nationals MP announced he would move a resolution ousting Mr Joyce as party leader.
The warning from Andrew Broad, member for the Victorian seat of Mallee, is the first public sign of a move against Joyce since his affair with a staffer was revealed.
Earlier today speaking from Washington, Prime Minister Malcolm Turnbull dodged questions about whether he wanted Joyce to remain as the Nationals leader.
"Barnaby Joyce is the leader of the National Party of Australia. As leader of the National Party of Australia in a Coalition government, he is my Deputy Prime Minister," Turnbull said.
"The leadership of the National Party is a matter for the National Party and I've been at great pains to stress that I have not, nor has my party, sought to influence in any way the deliberations of the National Party, any more than I'd expect the National Party to seek to influence deliberations of the Liberal Party."
Turnbull was accused of making "a shocking error of judgment" with Joyce, who has four daughters and back by calling the prime minister "inept".
Colleagues of Joyce were reportedly growing increasingly frustrated with his handling of the scandal.
Yesterday, the Nationals confirmed a formal sexual harassment complaint had been made against Joyce.
"The Federal Party can confirm a formal complaint has been received," Nationals federal director Ben Hindmarsh said in a statement. "All complaints are taken seriously and treated with strict confidentiality and given due process."
Nationals MP Michael McCormack has been tipped as the next Nationals leader.
While Broad's comments yesterday marked the first time a Nationals MP has publicly turned on Joyce, the National Party in Western Australia earlier this week effectively told him to resign.
In a statement, Mia Davies, the leader of the Nationals in WA, said she had contacted Joyce to tell him he was causing "ongoing damage" to the party and his position as Federal Leader was "no longer tenable".
"Mr Joyce's actions have caused pain for his family but it is the ongoing damage he is causing The Nationals organisation that is of greatest concern to me as WA Leader," Davies said.
"The Nationals brand across Western Australia has suffered as a result of Mr Joyce's actions and he has become a distraction at both a federal and state level.
"My parliamentary colleagues and I have urged Mr Joyce to consider his position as leader in the best interests of the federal party and state branches.
"It is the view of the Parliamentary National Party of Western Australia that Joyce's position as a Federal Leader is no longer tenable."
It all comes as the Deputy PM and Campion said they feared their baby son would be viewed "somehow less worthy than other children", in an interview with Fairfax Media.
The couple claimed they had been "forced out" of their rent-free townhouse in Armidale due to media intrusion as they appealed to politicians and members of the public to give them privacy.
"It's time to move on," the Nationals Leader told Fairfax Media.
