Taxpayers spend 6.1 billion hours a year just to comply with the federal tax code, according to experts at a Tax Foundation event on Monday.

Pete Sepp, president of the National Taxpayers Union, said that tax compliance costs taxpayers $234 billion per year in direct costs and lost productivity.

"The problem is the status quo—thinking that, well, if we don't do tax reform this year it will just be that bad," Sepp said. "No, the status quo is not the static quo—it's going to get worse."

"The paperwork burden inventory at the Office of Management and Budget related to Treasury is expected to rise by another 2 billion hours in the next few years," he said. "One-third added to that, we're looking at tax compliance costs of north of $400 billion a year."

Sepp admitted that the failure of the Republican health care reform bill, with its projected deficit reductions, will make it more difficult for Republicans to pass a tax reform bill.

"This is the important point right now, it's an especially important one in this current post-Obamacare repeal environment," Sepp said. "We now have about a trillion dollars of baseline problem now that we didn't think we would have before assuming Obamacare was going to be repealed."

"That's going to make tax reform a much tougher task," he said. "It also means we're going to have to find other ways of making every single simplification measure count, more so than it ever would have needed to count in the past."

House Republican leadership withdrew the American Health Care Act on Friday ahead of a scheduled vote, following President Trump's request that the legislation be pulled. Trump said tax reform would be the next item on the agenda.

"We are going, right now, for tax reform," Trump said. "Which we could've done earlier, but this really would've worked out better if we could've had Democrat support."

"So we'll probably … start going very strongly on big tax cuts," Trump said. "Tax reform—that will be next."

Trump has proposed cutting the corporate tax rate from its current level of 35 percent to 15 percent, reducing the number of individual tax brackets from seven to three, and changing the structure of tax deductions. He vowed to cut personal income taxes for all Americans.