"If I'm not under audit, I would do it, I have no problem with it, but while I'm under audit, I would not give my taxes", Trump said.
Financial Services Chairwoman Maxine Waters, D-Calif., citing a long list of Trump administration officials who have departed, pressed Mnuchin on whether he was anxious about being fired if he complied with the request.
Democrats are pursuing Trump's returns under a legal authority that aims to prevent interference from the White House on the Treasury's decision whether to release the tax returns, in what the White House chief of staff has called a "political stunt". "We had obviously read in the press that we were expecting this".
There was a tense exchange between Treasury Secretary Steven Mnuchin and California Rep. Maxine Waters over whether Mnuchin could leave a committee hearing for another engagement on Tuesday. He said that members of Treasury's legal team had had consultations on the matter before the tax return request was made but that the Treasury officials had not sought any type of permission to release the returns.
"I think that there was any communication with the White House about this is deeply troubling and certainly violates the spirit of the law, if not the letter of the law, and I think we need to get to the bottom of this", she told Mnuchin at the afternoon hearing.
But Democrats have long wanted Trump's tax returns to see what foreign financial dealings he may have, whether he always followed the law, and if he benefited from the 2017 Republican tax overhaul.
Mnuchin had said on Tuesday that Treasury Department lawyers had held "informational" discussions with the White House about an expected request for the returns, a step that Democrats criticized as uncalled for under the law.More news: Magic Johnson Steps Down as Lakers President
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"We intend to review your request carefully", he adds.
IRS Commissioner Charles Rettig told lawmakers that "we're working on" a response to a request from Ways and Means Committee Chairman Richard Neal. "It will be embarrassing if I keep this person waiting", he said, per CNN.
"I built a great company, one of the best companies, I have some of the greatest assets in the world, I did a good job, and now, frankly, I don't care about them, I only care about the United States", Trump said Wednesday.
Trump declined to release his records while running for president in 2016, breaking with decades of precedent.
Ever since President Richard Nixon was found to have understated his tax liability in the early 1970s, it has become common practice for presidents to release their tax returns.
Trump has given a range of explanations for why he has not released his tax returns.
When Nixon was first audited by the IRS, he was given a clean bill on his returns, but a subsequent audit of the same returns found that he owed almost $500,000 in additional tax on interest.
Democrats want access to the returns as part of investigations into Trump's business dealings and his campaign. The law says that if he wants the taxes, he should get them.