'It's none of your business': George Stephanopoulos and Donald Trump have testy exchange on tax returns

ABC's George Stephanopoulos pressed Donald Trump on Friday in one of the most combative exchanges yet over the Manhattan billionaire's tax returns.

Trump, who has suggested he might not release his returns before the November election, largely refused to budge.

"It's none of your business," Trump said when the ABC host asked about his tax rate. "You'll see when I release, but I fight very hard to pay as little tax as possible."

The presumptive GOP nominee has faced increased scrutiny over releasing his tax returns since he told The Associated Press on Tuesday that he wasn't planning on releasing his tax returns ahead of the election, citing an ongoing audit. He said he would release them after the audit is completed.

"There's nothing to learn from them," Trump said, adding that he doesn't believe voters are interested.

During Friday's interview, Stephanopoulos told Trump that voters "have a right" to see his returns before they make a decision on who they will cast a ballot for.

"I don't think they do, but I do say this: I will really gladly give them," Trump said.

He suggested he would unveil the returns once the audit is complete and that he hoped it would come before the election.

But "you're not going to learn anything," he said.

The ABC host then pressed Trump on why he previously released his tax returns while under an audit in hopes of getting a casino license, as reported by CNN.

"Well because at the time it didn't make any difference to me. Now it does," Trump said.

"I built a massive business and want to make sure everything's perfect. And it's a routine audit, and I want to get through the audit first," he continued. "And there have been many presidents who have not released their tax returns."

Stephanopoulos interrupted Trump, saying that each major party nominee since 1976 has released their returns. 

"Right, but before 1976 people didn't do it," Trump responded. "It used to be a secret thing. I don't want it to be secret, but I do want the audit to get finished."

Trump has been criticized by both sides of the aisle over his hesitance to release the returns.

Mitt Romney, the 2012 GOP nominee, wrote a lengthy Facebook post Wednesday ripping the real-estate magnate, saying his current refusal could signal a"bombshell of unusual size" existing in the tax returns.

"It is disqualifying for a modern-day presidential nominee to refuse to release tax returns to the voters, especially one who has not been subject to public scrutiny in either military or public service," Romney wrote on Wednesday.

"Tax returns provide the public with its sole confirmation of the veracity of a candidate's representations regarding charities, priorities, wealth, tax conformance, and conflicts of interest," he continued. "Further, while not a likely circumstance, the potential for hidden inappropriate associations with foreign entities, criminal organizations, or other unsavory groups is simply too great a risk to ignore for someone who is seeking to become commander-in-chief."

Democratic frontrunner Hillary Clinton was also quick to call out Trump for his refusal to release the returns. She told a crowd at a New Jersey rally that releasing the returns "is kind of expected" when you're a major party nominee. 

"My husband and I have released 33 years of tax returns, we've got eight years on our website right now," she said. "So you have got to ask yourself, why does he not release them?"

Trump fired back at Clinton in the Friday interview for the criticism. 

"I sort of have to laugh when Clinton says it," he said. "Mrs. Clinton said that I should give my tax returns. What about all the missing emails that she's got? When is she going to give the missing emails? Or her Goldman Sachs speeches, when is she going to give that? Very great hypocrite."

Watch clips from the exchange below: