A Trump administration official said Monday that federal income tax refunds would indeed go out despite a large part of the government being shut down.

Russell T. Vought, acting director of the White House Office of Management and Budget, told reporters about the development in a briefing.

"Tax refunds will go out," Vought said.

There have been growing concerns that tax refunds might be delayed as 800,000 federal workers are either furloughed or working without pay as President Donald Trump and Congress are mired in a standoff over funding for a southern border wall.

Only about 12 percent of IRS staff is expected to continue working through a shutdown, according to the agency's plan, which means certain functions such as answering taxpayer questions would be curtailed. The IRS is still working on contingencies if the shutdown continues.

"The processing of returns and customer service — most of those employees have been furloughed," said Nicole Kaeding, director of federal projects at the Tax Foundation.

"How will they bring those employees back, and will they be compensated while they're working?" she asked. "Those are some large questions that haven't been answered, even though they said refunds would be processed."

That makes this a stressful time for accountants — and their clients. "The October 2013 shutdown caused a lot of angst for practitioners," said Edward Karl, vice president of taxation at the American Institute of CPAs.

"If there were some issue and you needed to contact the IRS, you couldn't get them," Karl said. "There were many folks concerned about that."

Meanwhile, House Ways and Means Committee staff told The New York Times on Monday that they were struggling to get clarity from administration officials, many of whom are out on furlough.

"We keep trying to call people at IRS and Treasury," said Daniel Rubin, a spokesman for the Ways and Means Committee, "and there's no one there."