Existing mortgages under the old cap would retain their deductions, according to an outline of the plan.
A key test will be how House leaders deal with the state and local tax deduction, the first flash point in the debate.
House Ways and Means Chairman Kevin Brady said today he expects to announce a deal on the state and local tax deduction.
Congress is trying to ram through a bill that would reshape the U.S. economy in just a few short weeks.
Sharp divides remain within Congress and the GOP over the tax proposal.
The president is taking a second look at proposal to do away with state and local tax deductions.
Several other GOP senators could become obstacles to President Trump's effort to rewrite the tax code.
One nonpartisan study shows taxes would go up for almost 30 percent of people making $50,000 to $150,000.
They want tax reform support from high-tax states like California, New York and New Jersey.
GOP officials argue the plan is crucial for boosting economic growth; Democrats will paint it as a giveaway to the wealthy.