A day after rolling out a GOP tax reform bill, the House Republican in charge of writing that plan said he would offer 'additional' changes to the bill early next week, and left open the possibility that provisions dealing with the Obama health law might be added to the measure as well.

"At the start of our markup on Monday, I will also offer an additional amendment making more substantive improvements to the bill," Rep. Kevin Brady (R-TX) said in a statement from the House Ways and Means Committee, as the panel issued some technical changes to the measure, which now weighs in at 425 pages.

In that announcement, Brady, the Chairman of the House Ways and Means Committee, didn't expand on what "substantive improvements" might still be made to the bill, but in an event with Politico on Friday afternoon, Brady opened the door to provisions that could be drawn from the ill-fated GOP effort to overhaul the Obama health law.

"No decisions have been made," Brady said at the Politico event, "we're listening to the members and certainly the President as well."

What could be in play is a provision that would zero out the tax penalty for the individual mandate, which requires people to have health insurance coverage, or pay a tax penalty to the Internal Revenue Service.

"The President feels very strongly about including this at some step," Brady said at the Politico event.

In recent days, President Donald Trump has made clear that he wants lawmakers to look at the possibility of adding in provisions on the Obama health law as well - nothing on Obamacare was included in the original draft of the tax reform bill.

When it comes to the GOP effort to overhaul the Obama health law, which ran aground earlier this year, there would be no parliamentary impediment to adding some of those health care provisions to this bill, as long as they followed the rules under budget reconciliation, and that the overall tax reform bill does not increase the deficit by more than $1.5 trillion over the next ten years.

The Congressional Budget Office has found that repealing the individual mandate penalty under the Obama health law would decrease the deficit by $416 billion over ten years, meaning the inclusion of that provision could help 'pay for' other tax cuts.

That same report from the CBO says that getting rid of the individual mandate would also have a broader impact, causing "a substantial reduction in the number of people with health insurance."