David Jackson

USA TODAY

Campaign chairman Paul Manafort resigned from Donald Trump's team Friday, less than a week after the candidate reshuffled his staff and amid news reports about Manafort's past political activity for pro-Russian elements in Ukraine.

“This morning Paul Manafort offered, and I accepted, his resignation from the campaign," Trump said in a statement. "I am very appreciative for his great work in helping to get us where we are today, and in particular his work guiding us through the delegate and convention process."

Trump added that "Paul is a true professional and I wish him the greatest success.”

Earlier this week, Trump brought on two new top campaign officials in a move largely seen as a sidelining of Manafort.

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Stephen Bannon, the executive chairman for Breitbart News, is the new campaign CEO, and pollster and consultant Kellyanne Conway is now campaign manager. Trump had planned to retain Manafort as campaign chairman, but the veteran consultant left instead.

Trump announced he would accept Manafort's resignation while en route to Louisiana to tour flood damage.

This is the second change at the top of Trump's campaign in a little more than two months. Trump fired campaign manager Corey Lewandowski in June, a time at which Manafort ascended to the top of the organization.

The New York businessman brought Manafort into the campaign in March to organize the Republican nominating convention, including the prospect of a delegate challenge by "Never Trump" opponents. Manafort wound up running the campaign but took criticism over continuing Republican opposition to Trump and complaints about the candidate's lack of discipline and repeated attacks on GOP leaders.

Manafort leaves the campaign amid a rising number of news reports about his past work for pro-Russian political elements in Ukraine. While his work overseas has been no secret, there are new stories about allegedly secret cash payments that Manafort has denied. Democrats and others criticized Manafort for working against reformers who wanted Ukraine to focus on the West, not Russia.

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Aides to Democratic candidate Hillary Clinton attributed Manafort's resignation to "the disturbing connections" with pro-Kremlin forces, including Russian President Vladimir Putin. "You can get rid of Manafort, but that doesn't end the odd bromance Trump has with Putin," added Clinton campaign manager Robby Mook.

The departure from Trump's team did not surprise political consultants.

"It had to happen," said Republican consultant Bruce Haynes, founding partner of Washington-based Purple Strategies. "The revelations about the Ukrainian involvement put the consultant in a position where he was overshadowing the campaign and choking its ability to deliver its message."

Texas-based political consultant Matt Mackowiak said Trump "needed Manafort to leave over the Ukraine revelations. And now he has."

Eric Trump, the candidate's son, said in an interview to be broadcast Sunday on Fox News Channel's Sunday Morning Futures that Manafort did an "amazing" job for the campaign, but "I think my father didn’t want to be, you know, distracted by, you know, whatever things Paul was dealing with."

In another sign of a new direction in the campaign, Trump on Thursday made an unusual admission of regret for some of his past comments.

"Sometimes, in the heat of debate and speaking on a multitude of issues, you don't choose the right words or you say the wrong thing," Trump told backers in Charlotte. "I have done that — and, believe it or not, I regret it ... And I do regret it — particularly where it may have caused personal pain."

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Trump, who has been accused of offending Mexicans, Muslims, immigrants, the disabled and fellow Republicans such as John McCain during a campaign that began in June 2015, did not specify which comments he regretted and said at one point that journalists have often taken him "out of context." Throughout the campaign, Trump has generally refused to apologize for remarks viewed as insensitive or insulting.

It is unusual to make major organization changes this late in a campaign, but Haynes said Trump "simply cannot afford to have any more drama" little more than 80 days before the election against Clinton.

Haynes also said it is not too late for a race against a "flawed candidate" such as Clinton when voters want change.

"It's not like he's trying to catch Usain Bolt," Haynes said. "It's more like he's trying to catch Ryan Lochte."

Democrats said the repeated upheavals of Trump's campaign reflect dysfunction and disarray.

The pro-Clinton organization American Bridge cited news reports that Manafort will continue to be an ally of Trump's and added that "the Trump campaign will have plenty of Russia ties without him — starting with the Putin-admiring, NATO-hating candidate himself."

Republican consultant Liz Mair, a critic of her party's nominee, questioned how much difference staff changes would make in any event: "Trump is Trump. You can't make him more appealing, no matter who is running that particular clown show. He looks set to lose, and lose badly."