WASHINGTON — (CNN) President Donald Trump signaled Tuesday morning that he is not backing down from his feud with the NFL, claiming the league’s ratings are down in the wake of growing protests during the national anthem.

“Ratings for NFL football are way down except before game starts, when people tune in to see whether or not our country will be disrespected!” Trump wrote on Twitter.

He added, “The booing at the NFL football game last night, when the entire Dallas team dropped to its knees, was loudest I have ever heard. Great anger… But while Dallas dropped to its knees as a team, they all stood up for our National Anthem. Big progress being made-we all love our country!”

Ratings for NFL football are way down except before game starts, when people tune in to see whether or not our country will be disrespected!

— Donald J. Trump (@realDonaldTrump) September 26, 2017

The booing at the NFL football game last night, when the entire Dallas team dropped to its knees, was loudest I have ever heard. Great anger

— Donald J. Trump (@realDonaldTrump) September 26, 2017

The ratings picture is much more complicated than Trump’s tweet claimed. There was a big spike in viewership for the pre-game shows on Sunday, but it’s too soon to reach any conclusions about the effect of the controversy on viewership.

Early ratings from Sunday, which are incomplete and subject to change, showed that games on CBS were up compared to the same week last year, while games on Fox and NBC were down.

The day’s biggest broadcast, NBC’s “Sunday Night Football,” declined about 10% from the equivalent game last year. But it’s hard to say whether that was due to Trump, the anthem protests, competition from other shows or the fact that the Redskins’ lopsided victory over the Raiders made for a relatively unexciting match-up.

More reliable viewership data for Sunday’s games will come in on Tuesday.

Trump entered the controversy about the NFL at a Friday night rally when he went after the league and attacked players who have been kneeling or sitting during the national anthem to draw attention to social justice issues, including police brutality.

“Wouldn’t you love to see one of these NFL owners, when somebody disrespects our flag, to say, ‘Get that son of a bitch off the field right now, out, he’s fired. He’s fired,'” Trump told a crowd in Alabama.

The comments drew widespread criticism from players and team owners.

On Saturday, he called for NFL fans to boycott games unless the league fired or suspended players who refuse to stand for the national anthem, and has tweeted more than a dozen times about the matter.

At a private dinner with conservative leaders Monday evening, Trump said his NFL comments have “really caught on,” according to an attendee, who noted the President told them, “I said what millions of Americans were thinking.”

White House chief of staff John Kelly, however, was not pleased with the resulting firestorm over the weekend, according to two administration officials. But in a brief interview Monday evening, Kelly told CNN he is “appalled” by what he sees as a lack of respect for the flag and national anthem.

“I believe every American, when the national anthem is played, should cover their hearts and think about all the men and women who have been maimed and killed,” Kelly said. “Every American should stand up and think for three lousy minutes.”

His son, Robert Michael Kelly, was killed in combat in Afghanistan in 2010.

Kelly declined to talk about the President’s decision to wade into the issue. White House officials say they believe this will blow over, but did not know how long the President would keep it alive.

White House press secretary Sarah Sanders defended the President’s comments from the briefing room podium Monday, saying they were not intended to be divisive.

“This isn’t about the President being against anyone,” Sanders said. “This is about the President and millions of Americans being for something” — like “honoring our flag.”

The President has a jam-packed Tuesday. He receives a briefing on hurricane recovery efforts from homeland security adviser Tom Bossert, meets with bipartisan House Ways and Means Committee members, and welcomes Spanish President Mariano Rajoy before traveling to New York for a Republican National Committee fundraiser.

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