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Trump's campaign says Stone was fired because he was using the campaign to seek publicity for himself

But a source tells CNN that tensions between the two men spiked after Trump's debate performance

CNN  — 

Donald Trump’s campaign said Saturday it has fired top political adviser Roger Stone – who promptly denied being let go and insisted he had quit.

Stone’s disassociation from the Trump operation highlights the campaign’s seeming lack of veteran political advisers, even as the 2016 season is ramping up in earnest. And the dispute opens a window into two different factions of the campaign: one side that wants to maintain Trump’s high visibility by capitalizing on his public feuds and bombastic rhetoric, and another that wants to pull the candidate toward more disciplined political strategy.

The episode caps a tumultuous few weeks for Trump’s presidential campaign, which recently cut ties with two men accused of writing inflammatory Facebook posts. Trump, who is currently leading national polls, delivered an explosive performance at the first GOP debate in Cleveland on Thursday, and went on to make inflammatory comments about Fox News host Megyn Kelly in an interview on CNN on Friday night.

“Mr. Trump fired Roger Stone last night. We have a tremendously successful campaign and Roger wanted to use the campaign for his own personal publicity. He has had a number of articles about him recently and Mr. Trump wants to keep the focus of the campaign on how to Make America Great Again,” a campaign spokesperson said in a statement.

Stone, however, told CNN that he “categorically denies” being fired,and provided what he said was his resignation letter.

“Unfortunately, the current controversies involving personalities and provocative media fights have reached such a high volume that it has distracted attention from your platform and overwhelmed your core message. With this current direction of the candidacy, I no longer can remain involved in your campaign,” the letterto Trumpsays.

Stone added: “I care about you as a friend and wish you well. Be assured I will continue to be vocal and active in the national debate to ensure our nation does not again turn to the failed and distrusted Bush/Clinton families.”

Trump’s campaign manager, Corey Lewandowski, said the team never saw Stone’s letter. For his part, Stone tweeted Saturday afternoon that he “fired Trump.”

RELATED: Donald Trump’s ‘blood’ comment about Megyn Kelly draws outrage

“Sorry @realDonaldTrump didn’t fire me- I fired Trump. Diasagree [sic] with diversion to food fight with @megynkelly away core issue messages,” the tweet read.

The Washington Post first reported that Stone was no longer a part of Trump’s campaign.

Matt Mackowiak, a Republican political consultant and close friend of Stone’s, told CNN that Stone was deeply disappointed with Trump’s debate performance Thursday.

Stone, a former aide to President Richard Nixon who has known Trump for several decades, helped with the candidate’s debate preparations. He had hoped that Trumpwould stay focused and disciplined, sticking largely to issues like illegal immigration and trade. Instead, Stone concluded that Trump had taken the debate to a “circus-like place.”

The working relationship between Stone and Trump became further strained when Trump made controversial comments about Kelly in an interview with CNN’s Don Lemon.

“You could see there was blood coming out of her eyes,” Trump told Lemon. “Blood coming out of her wherever.”

“Calling into CNN and making outrageous comments about Megyn Kelly and making it even more of a circus than it already is, Roger just felt like he couldn’t stand by him,” Mackowiak said.

Mackowiak also said Stone had planned to announce his resignation Saturday night, and when Trump got word, the candidate announced he had fired Stone.

One Trump associate and friend also told CNN that existing tensions between Stone and Trump reached a breaking point following the candidate’s explosive debate performance.

“He has been disenchanted with Trump for a few weeks now,” the associate said, citing Stone’s perception that Trump’s candidacy lacked “seriousness.”

According to this source, Stone was unhappy with Trump’s conduct on the debate stage in Cleveland, and when Stone shared these thoughts with Trump, the billionaire businessman “didn’t want to hear it.”

Another Republican source close to Stone said the adviser resigned in part because he grew frustrated with the campaign’s refusal to focus on policy specifics and conduct polling.

“Roger has been trying to press the campaign to get specific on issues, to poll, to run an actual campaign, while others in Trumpland have been egging him on to continue to engage in these political food fights like the Megyn Kelly incident,” the Republican source said.

Speaking with CNN’s Poppy Harlow late Saturday afternoon, Stone again insisted he quit, saying he felt he “was having no impact.” He said he hoped Trump would return to speaking about the “big picture” issues, such as trade and immigration, that helped fuel his rise to the top of GOP polls.

But Stone refused to elaborate in greater detail about how his relationship with the campaign ruptured, saying he had “no intention about talking about internal campaign deliberations.”

He did say, however, that he and Trump remain friends, and although he isn’t a registered Republican, said he would continue to back a Trump bid.

“If I had the opportunity to vote for him in the primaries, I would,” he said. “I still think he is the right man to make America great again.”

CNN’s Jeff Zeleny contributed to this report.