On Saturday, Donald Trump threatened to revoke the credentials of The New York Times after the newspaper published a report detailing the "failing" effort by Republican Party operatives to "save Mr. Trump from himself."

On Sunday, the Republican presidential candidate doubled down, slamming the Times on Twitter and vowing to never change.

The failing @nytimes talks about anonymous sources and meetings that never happened. Their reporting is fiction. The media protects Hillary! — Donald J. Trump (@realDonaldTrump) August 14, 2016

The failing @nytimes, which never spoke to me, keeps saying that I am saying to advisers that I will change. False, I am who I am-never said — Donald J. Trump (@realDonaldTrump) August 14, 2016

If the disgusting and corrupt media covered me honestly and didn't put false meaning into the words I say, I would be beating Hillary by 20% — Donald J. Trump (@realDonaldTrump) August 14, 2016

My rallies are not covered properly by the media. They never discuss the real message and never show crowd size or enthusiasm. — Donald J. Trump (@realDonaldTrump) August 14, 2016

"The newspaper's going to hell," Trump told a rally Saturday at Sacred Heart University in Fairfield, Conn. "They've got a couple of reporters in that newspaper who are so bad — I mean lack of talent. But it's going to hell.



"So, I think maybe what we'll do, maybe we'll start thinking about taking their press credentials away from them," the Republican nominee added, drawing cheers from the crowd.



"Maybe we'll do that. I think so. I think so.



"When they write dishonest stories, we should be a little bit tough, don't we agree?"



Many in the audience yelled "yeah."



The Times report, by Alexander Burns and Maggie Haberman, detailed efforts by staffers to keep Trump on script, focus more on policy and tone down his inflammatory rhetoric and combative style.



It was based on interviews with 20 Republicans, many of whom insisted on anonymity to avoid clashing with him," according to the Times.



The article also described a meeting Trump had with GOP political consultant Karl Rove and casino magnate Steve Wynn during the primaries — from which Rove emerged "stunned" that the nominee knew little about campaign basics.



Trump slammed the Times for using anonymous sources, saying "I don’t think they have any names."



In an overall attack on the press, Trump said that it was his biggest competitor in this campaign, not Hillary Clinton.



"I'm not running against crooked Hillary," he said. "I’m running against the crooked media.



"That’s what I’m running against, I’m not running against crooked Hillary."

Paul Manafort, the Trump campaign chairman, also pushed back against the media during an appearance Sunday on CNN.

"Contrary to the New York Times's nameless sources story, the campaign is moving forward and very strong," he said. "We raised over $132 million in the last two months."

He noted that Trump had visited key battleground states such as Pennsylvania, Ohio and Florida repeatedly and was "starting to get traction in those states."

However, recent polls have shown Trump's numbers sagging badly in those battleground states, notably hurt by his critical comments about the Muslim parents of a fallen US soldier, and what some saw as his suggestion that "Second Amendment groups" -- gun lovers -- take their dislike for Clinton into their own hands.

Manafort repeated the Trump claim that his Second Amendment remark was meant purely as an exhortation to vote.

But even one of Trump's top advisers, Senator Jeff Sessions of Alabama, conceded Sunday that the candidate needed to communicate "more effectively."

"He's got to wrestle in his own heart, how does he communicate who he is, what he believes, the change he thinks he can bring to America," he said on ABC.

"He does need to communicate -- and I think he can -- more effectively."

The CNN interviewer also asked Manafort about mounting pressure on Trump to release his tax returns after Clinton released hers on Friday.

The channel broadcast video of Trump urging Mitt Romney, the Republican candidate in 2012, to release his returns at the time, saying, "If you didn't see the tax returns, you would think there is almost, like, something wrong."

Manafort repeated Trump's explanation that he is under audit by the Internal Revenue Service.

"When that's completed, he'll release the returns," Manafort said, adding that Clinton's returns showed income coming from "people who benefited from her State Department term as well," referring to her time as secretary of State.

"I haven't seen stories on that yet."

Trump has revoked the press credentials of several media outlets, including Politico, The Washington Post and The Huffington Post.



"I'm no fan of the Washington Post, although they have been much nicer lately, I must say," Trump said Saturday. "Maybe I'll let them back in. they’ve been much better."



He also ripped CNN for its coverage of him saying that President Barack Obama was the "founder" of the Islamic State — a remark he later said was sarcastic, "but not that sarcastic."



"CNN is so disgusting," Trump said. "Their ratings are going down big league.



"You know why? Because I refuse to be interviewed. And I get high ratings, what can I say?



"These people are so dishonest."



He later praised an article from The New York Post, which detailed his contributions as a developer to New York City.

Material from AFP was used in this story.