WASHINGTON — President Donald Trump raised expectations Sunday about Republicans’ timetable for completing tax reform, indicating he expects the as-yet unwritten overhaul of the tax code on his desk by Thanksgiving.

“I want to get it by the end of the year, but I’d be very disappointed if it took that long,” he said on Fox’s “Sunday Morning Futures With Maria Bartiromo.” He said lawmakers should forgo their Thanksgiving break if they can’t send him a measure by then.

Republican leaders have painted an optimistic picture of the overhaul’s chances, saying they hope to have it done by the end of the year. But many have predicted a vote could roll over into 2018, particularly with Trump’s abrupt addition of several issues to their agenda.

That includes coming up with a legislative fix for the legal status of immigrants brought to the country illegally as children, reaching a bipartisan agreement to stabilize health insurance markets after Trump halted subsidies to insurance companies to offset co-payments and deductibles for low-income people, and responding to Trump’s refusal to recertify the Iranian nuclear deal.

The tax plan Republican leaders and the White House have laid out calls for reducing tax rates on corporations from 35 percent to 20 percent, and consolidating individual tax rates to 12 percent, 25 percent, 35 percent and possibly one higher bracket for the wealthy. Income brackets for those rates have yet to be set.

Actual text of a tax overhaul bill hasn’t been written, much less become public. Members of Congress haven’t reached consensus on what cuts to make or where to make them. Trump signaled tweaks are still being made.

“There’s tremendous spirit for it, not only by the people we’re dealing with in Congress, but for the people out there that want to see something,” Trump said. “We’re adjusting so that there’s no way that the middle class doesn’t greatly benefit.”

The president, who had a telephone call with House GOP members Sunday to offer encouragement and urge them to move quickly, confirmed in the Fox interview that Republicans are considering adding a tax bracket for the rich to their plan, saying it would provide a bigger benefit for the middle class.

House Speaker Paul D. Ryan indicated Friday the extra bracket was Trump’s idea. Trump seemed less willing to accept credit but acknowledged the idea was in response to his request for more help for the middle class.

“I would rather do that than do anything to hurt the middle class,” Trump said.

On “Fox News Sunday,” White House Budget Director Mick Mulvaney downplayed adding the bracket and said it was an idea that originated in Congress to help ease passage.

“What we’ve just said at the White House is, ‘Look, we are agnostic about that. It’s not a big piece for us ... . It’s not what’s driving this for the White House,’ ” he said.

Still unclear is how Republican leaders will persuade rank-and-file members who came to Congress pledging to reduce the size of the deficit to vote for a tax cut plan that will increase the deficit by $1.5 trillion in 10 years.

The beginnings of their talking points were clear Sunday, with Senate Majority Leader Mitch McConnell, R-Ky., saying on CNN’s “State of the Union” that the tax package will create so much economic growth it will begin to pay down the nation’s debt. There’s little historical evidence that tax cuts pay off in long-term economic growth.

“This is a tax reform bill designed to make America grow more,” McConnell said.

After failing to get an overhaul of the Affordable Care Act through both chambers, Republicans need a legislative victory this year. Trump said that failure on healthcare will spur his party to get tax reform accomplished.

“I will say the fact that health care is so difficult, I think, makes the taxes easier. The Republicans want to get it done,” he said.

Trump predicted Republicans will have the votes they need on taxes, saying libertarian-leaning Sen. Rand Paul, R-Ky., will vote for it. Some in the White House have indicated they were worried Paul would take a hard-line stance against the GOP plan because it would increase the federal deficit. But the senator tweeted Friday he’s “all in.”

“I think that Rand Paul actually is going to vote for the tax cuts ... . We had tremendous enthusiasm this time. Health care, I was told was tougher but it was close. I mean, so far, I would say it’s not even a contest,” Trump said.

Trump has distracted from legislative issues repeatedly in the first 10 months of his administration, most recently bickering online with Republican senators including Bob Corker, the Republican chairman of the Senate Foreign Relations Committee. But Trump dismissed the idea he’s getting in his own way.

“Sometimes it helps, to be honest with you,” Trump said. “Actually sometimes it helps. Sometimes it gets people to do what they’re supposed to be doing. And you know, that’s the way it is.”

Trump said having a direct line to his millions of Twitter followers guarantees his meaning won’t be muddled by the media.

“When somebody says something about me, I am able to go bing, bing, bing and I take care of it,” he said. “The other way, I would never be able to get the word out.”

He also touched on criticism of a condolence call he made to Myeshia Johnson, widow of Army Sgt. La David T. Johnson, who was killed in Niger this month. Trump and Johnson’s congresswoman and longtime mentor, Rep. Frederica Wilson of Florida, publicly have argued about the content and tone of the call. White House Chief of Staff John F. Kelly, who lost a son in Afghanistan in 2010, gave an emotional defense of the call Thursday in the White House briefing room.

“He was so offended, because he was in the room when I made the call and so were other people,” Trump said of Kelly’s reaction. “And the call was a very nice call. He was so offended that a woman would be — that somebody would be listening to that call. He actually couldn’t believe it. Actually, he said to me ‘Sir, this is not acceptable. This is really not.’ ”

Trump also shot back at the family’s criticism that the president didn’t seem to know Johnson’s name when he called.

“By the way, I spoke of the name of the young man and it was a really — it’s a very tough call. Those are the toughest calls,” he said.