Senate Republicans are discussing adding provisions to their tax bill that could trigger up to $350 billion in automatic tax increases over 10 years beginning in 2022, according to two people briefed by congressional staff members on the plan.

A third person familiar with the emerging proposal confirmed the details. Republican senators including Bob Corker of Tennessee and James Lankford of Oklahoma have sought the trigger provision as a way to prevent the tax cuts in the Senate bill from increasing federal deficits.

Representatives for Corker and Lankford didn’t respond to requests for comment. A staff member in Senate Majority Leader Mitch McConnell’s office declined to comment. Senate leaders hope to hold a floor vote on the bill on Thursday or Friday. The measure is estimated to reduce federal revenue by more than $1.4 trillion over 10 years before accounting for any economic growth it might produce.

Here’s how the people described the plan, which may still be subject to change:

Tax increases would be triggered if revenue fell short of a specified threshold. That threshold consists of the revenue baseline that’s anticipated under current law over the next five years -- minus an amount that would have been lost under corporate expensing provisions that Congress has been allowing on a year-to-year basis. (The Senate bill would allow for full expensing of equipment purchases through 2022, at an estimated cost of $61.3 billion.)

The size of a tax increase would correlate to the size of any shortfall. It would come in the form of an increase in the corporate tax rate and a new tax on the difference between corporate book income -- that is, the income reported to shareholders -- and actual taxable income.

The Senate parliamentarian will have to decide whether the revenue trigger provision meets the Senate Byrd Rule, which wouldn’t allow for any provisions in the legislation that don’t have direct fiscal effects.

If trigger fails the Byrd rule, then an alternative plan would call for the bill to simply contain a tax increase or increases beginning in 2022. A future Congress would have to repeal the increase.

This article was provided by Bloomberg News.