NEW YORK — (CNN) Donald Trump is asking vice presidential hopefuls for their tax returns — even though he is not yet releasing his.

It is standard practice for potential vice presidential picks to submit detailed financial paperwork, including tax returns, to the person who could choose them to serve as their No. 2 in the White House. But it would be unprecedented in modern times for that vice president to be the only one on the ticket who has disclosed theirs.

A Trump adviser confirmed Wednesday that presumptive Republican presidential nominee will require the men and women he is considering for his vice president to submit them to his vetting team.

The VP nominees’ records wouldn’t be made public. Trump, meanwhile, has said he will only release his when his routine audits come to a close — something he admits could come after Election Day.

Trump’s resistance to publicly releasing his tax documents leaves major questions for voters weighing a candidate whose campaign is staked on his business acumen and the fact that he says he is “very, very rich” — and would mark a major break with decades of precedent set by the nominees of the two major political parties.

Trump has maintained that there is little that people could learn from his returns. He has said that “I fight like hell not to pay” much in taxes, but he has declined to release the rate in advance.

“None of your business,” he told ABC’s George Stephanopoulos earlier this month.

That has been fodder for Hillary Clinton, whose aides have wondered aloud about what could be in the returns.

“Because when you run for president, especially when you become the nominee that is kind of expected,” Clinton said in New Jersey last week. “My husband and I have released 33 years of tax returns, we’ve got eight years on our website right now. So you have got to ask yourself, why does he not release them?”

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