A week before the 100 day mark of President Donald Trump's time in office, top administration officials say they are on the verge of releasing a sweeping plan to reform the nation's tax system, waving off questions about whether legislative troubles with a GOP health care proposal would foreshadow tax troubles as well.

Asked when the details of the plan would be released, Treasury Secretary Steven Mnuchin said, "Soon, very soon."

"We're very focused on it," Mnuchin said at a Washington, D.C. event sponsored by the Institute of International Finance.

"Big priority for the President - we will get tax reform done," Mnuchin added.

Earlier in the week, Mnuchin had backed off his vow to get tax reform through the Congress by the summer break that lawmakers take in August - his latest prediction is just a few months after that, at the end of the year.

Without giving away many details, Mnuchin did say the Trump tax plan would have either three or four tax brackets - there are currently seven - along with a streamlined tax system.

"Fundamentally, fewer brackets, less deductions, simpler tax code," said Mnuchin.

"This will be the most significant change to the tax code since Reagan," the Treasury Secretary added.

But nothing is on the schedule right now in the Congress on taxes, as when lawmakers return next week after an over two week break, they will have to immediately turn their focus to a funding measure to avoid a government shutdown next Friday night.