“Altering that would make it more difficult for American companies to compete in the global economy and harm job creation and long-term economic growth,” said Mac O’Brien, a spokesman for the group. “Fortunately, the discussion on tax reform is far from over.”

Similar concerns are emanating from Wall Street, with the American Bankers Association warning that a limitation on borrowers’ ability to deduct interest expenses could “adversely impact economic growth.”

Republicans have only slightly tipped their hand as to the overall structure of the tax rewrite. The plan would slash the corporate tax rate to 20 percent from 35 percent, and create a new 25 percent tax rate for “pass through” businesses such as partnerships, sole proprietorships and family farms.

It would also lower the top individual tax rate to 35 percent from 39.6 percent, while raising the bottom rate to 12 percent from 10 percent as it also doubles the standard deduction. The plan would eliminate many corporate “loopholes” and deductions, such as the state and local tax deduction. But it would also get rid of many provisions that are currently costly to the rich, like the estate tax and the alternative minimum tax.

The most politically fraught proposal is eliminating the state and local tax deduction, which allows taxpayers who itemize to write off their property, state and local taxes. The measure is particularly prized in blue states with high property taxes, but is also widely used in some Republican districts in Virginia, New Jersey and California.

Eliminating the deduction, which the real estate industry also opposes, would save more than $1 trillion over a decade and make room for the tax cuts. But Republican members of Congress in affected states have already expressed concern about the provision, and a plan that repeals the deduction could be impossible to pass.