(Bloomberg) -- White House officials outlined what one of themcalled an “aggressive” timetable Monday for getting a tax overhaul in place before the end of theyear.

A top White House legislative aide said the plan for a tax code rewrite is to start hearings and amarkup of the bill after Labor Day so a version can get through theHouse in October and the Senate in November.

He also said a 2018 budget resolution -- the first step to get atax bill passed without Democratic support --would be agreed upon in September or October.

“So that, I think, is an aggressive schedule, but that is ourtimetable,” White House legislative affairs chief Marc Short saidat a tax event in Washington sponsored by Americans forProsperity, a group backed by billionaire industrialistsCharles and David Koch.

National Economic Council Director Gary Cohn repeated themessage, saying before a listening session with real estateindustry members that the administration and congressionallawmakers were in a “heavy drive toward tax reform.”

Treasury Secretary Steven Mnuchin said at the AFP event that theplan was to have a tax bill “start going through the normalprocess” beginning on Sept. 1.

The White House has said it wants to lower corporate andindividual tax rates, eliminate deductions and simplify thecode.

Despite the officials’ assurances on timing, many obstacles andunanswered questions remain about how to offset cutting tax rateswith new revenue so the tax changes can be permanent undercongressional budget rules.

Immediate expensing

Short said that the White House probably wouldn’t be pushing forso-called full expensing, which would allow companies to fullydeduct their capital spending from income immediately instead ofover years.

House Speaker Paul Ryan had pushed for full expensing, alongwith the controversial border-adjusted tax on imports, in his taxblueprint released last June.

“The message is: It may not be perfect for everything we want,but it’s going to be really, really good for the economy and a lotbetter than what we have,” Mnuchin said.

A tax overhaul will require a delicate balancing act, and onethat has bedeviled negotiators in the past.

A major tax revamp hasn’t been passed in more than threedecades, and the Trump administration is under pressure afteranother legislative effort -- repealing and replacing the 2010health-care legislation -- has produced no results.

Short said the president plans to do more traveling to pitch atax overhaul than he did for the health-care effort. “From a travelperspective, you’ll probably see more activity,” he said.

Few details of the planned tax code rewrite have emerged fromweekly, closed-door tax meetings between Trump’s advisers andcongressional leaders, leading analysts to fear that any tax-ratecuts may be shallower than many hoped.

That would jeopardize Trump’s goal of spurring job creation andeconomic growth, and do little to prevent U.S. companies fromshifting their income and tax liabilities offshore to lower-taxcountries, economists say.

Negotiators have made “enormous progress” despite being “prettyfar apart” when the effort to rewrite the tax code began during thetransition, Cohn said Monday morning.

Still, he added: “We’ve got to get a lot done in the next threeto four weeks.”

Inflated chicken

About 50 protesters demonstrated outside the AFP event whereMnuchin and Short spoke.

They were accompanied by large props including an inflatedchicken sporting a hairstyle like Trump’s -- a reference to theprotesters’ saying the president is afraid to release his taxreturns.

Trump has departed from 40 years of tradition for presidents bydeclining to make his returns public. He has said he’s under anaudit and won’t release the documents until that review hasconcluded.

The demonstrators held pre-printed yellow signs with slogansincluding “Medicaid Not Millionaires” and “No Tax Cuts For Trump.”They used bullhorns to tell stories about people who could beadversely affected by cuts in social programs if they’re used tohelp pay for tax changes.

Last week, White House officials and congressional leadersreleased a joint statement outlining their tax principles, with theonly real progress disclosed being that the border-adjusted taxwouldn’t be part of negotiations going forward.

That signaled a victory for retailers and other import-heavyindustries and for groups backed by the Koch brothers, whichopposed the measure.

The border-adjusted tax had helped Ryan and his allies proposelowering the corporate tax rate to 20 percent from the current 35percent. Trump has called for going even lower -- to 15 percent, atarget that may be far harder to achieve.

Senator Orrin Hatch, chairman of the tax-writing FinanceCommittee, tried to temper expectations on corporate rates whentalking to reporters Monday.

“The art of the doable is the threshold right now,” Hatch said.“Anywhere between 15 and 25 percent would be tremendous.”

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