President Trump, pitching his tax plan and other administration efforts to the Heritage Foundation's annual President's Club Meeting Tuesday night, claimed his administration has accomplished more in nine months than any administration in history.

"We have taken action to repeal the EPA's so-called clean power plan," he told the conservative crowd. "And we have ended, finally, the war on clean, beautiful coal. People going back to work, they're going back to work. Over the last nine months, we have removed job-killing regulations at a record pace. In fact, in nine months, we have done more, they say, than any president in history, and we're nine months. And there's more to come."

The president didn't clarify who had claimed his administration has accomplished more in that time frame than any other. Mr. Trump, there in part to pitch tax reform, made another claim Tuesday evening — that his tax plan will be the largest reduction in taxes in the country's history. The nonpartisan Committee for a Responsible Budget estimates it would likely be the fifth-largest in history, at best.

Get Breaking News Delivered to Your Inbox

Mr. Trump is having difficulty persuading even some in his own party of the merits of his tax plan, which simplifies tax brackets and lowers taxes on businesses, but will have a debatable impact on the middle class. Mr. Trump has said his plan will save the average middle class family $4,000 through changes to the tax code, but some critics point out that is no guarantee, and some middle-class families may pay higher taxes as a result of the plan. Voters are also skeptical. A recent CBS News Nation Tracker poll found most Americans believe the plan would benefit the wealthy, even as the White House pitches the plan as a boon for the middle class.

"At the heart of our plans is a tax cut for everyday, working Americans," Mr. Trump said Tuesday, adding his plain aims to make it so families can file taxes on a single sheet of paper.

Live updates from earlier below:

7:47 p.m. Trump says people will say "Merry Christmas" again

Mr. Trump, speaking to the conservative crowd in October, said he wants stores to say "Merry Christmas" again.

"Lets give our country the best Christmas present of all: massive tax relief," the president said.

"And you're gonna be saying Merry Christmas again."

7:43 p.m. Trump claims his plan is biggest tax cut in history of U.S.

The president claimed his tax plan will result in the largest tax cut in U.S. history, although he didn't specify how that would be the case.

7:39 p.m. "At the heart of our plans is a tax cut for everyday, working Americans," Trump says

The president touted some of the details of his plan, saying the goal is to cut the tax burden for the middle class. He also emphasized how he believes his plan will simplify the tax code, and allow families to file their taxes on a single sheet of paper.

"At the heart of our plans is a tax cut for everyday, working Americans," he said.

7:36 p.m. Trump: "They" say we have accomplished more than anyone else in 9 months

Mr. Trump touted that "they" believe his administration has accomplished more in nine months than any previous administration, although he gave no attribution to that person or group that might be.

7:29 p.m. Trump: We believe our American flag should be treated with respect

Mr. Trump, without discussing the NFL, alluded to the his controversy with the NFL. The president emphasized that the American flag must be treated with respect, and that the national anthem should be sung.

7:27 p.m. Trump: Progress must be built on a foundation of timeless truths

Mr. Trump, taking the stage, said he and others in the room share the same belief that the U.S. was founded on core principles, and must preserve U.S. heritage.

"Freedom of not a gift from government. Freedom is a gift from God," Mr. Trump said, using one of his classic speech lines.

Mr. Trump said he and others were present to make sure no threat, foreign or domestic, undermined those core American values.

"This is a time of great challenge for the world, but also, of great opportunity," Mr. Trump said.