President Trump laid into Arizona Sen. Jeff Flake again, speaking to reporters outside the White House Wednesday as he left on a trip to Texas.

'I remember the first time I saw him on television ... I assume he's a Democrat,' Trump said. 'Is he a Democrat? They said, "He's a Republican." I said, "That's impossible."'

Trump went on for several minutes saying the retiring GOP senator had 'done terribly' for Arizona and the president would 'be boosted' once Flake is out of his U.S. Senate seat.

In a dramatic floor speech Tuesday, Flake announced that he would not be running for re-election next year, saying he preferred to be untethered from towing the party line so he could speak out against Trump, who he labeled – without saying the president's name – 'reckless, outrageous and undignified.'

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President Trump again blasted Arizona Sen. Jeff Flake, who announced he would not run for re-election yesterday. Trump told reporters Wednesday that the first time he ever saw Flake he thought he was a Democrat

President Trump took a number of questions from reporters gathered outside the White House Wednesday and renewed his attacks, started on Twitter this morning, of Sen. Jeff Flake

President Trump's mini press conference took place just hours after Sen. Jeff Flake (pictured) did a number of morning TV hits, where he continued to criticize Trump

President Trump went after retiring Sens. Jeff Flake and Bob Corker on Wednesday using his Twitter account

THAT WENT WELL: Trump also tweeted about his Tuesday meeting with Senate Repubicans

Sen. Jeff Flake said he was done being 'complicit,' as he belongs to the same political party of President Trump and thus announced Tuesday he would no be running for re-election next year

Flake's break came the same day Tennessee Sen. Bob Corker renewed his tiff with Trump, also over the president's behavior.

As Wednesday began, Trump took to Twitter to air out his grievances against the two rogue and retiring GOP senators, who both faced tough re-election prospects.

'The reason Flake and Corker dropped out of the Senate race is very simple, they had zero chance of being elected. Now act so hurt & wounded!' Trump said.

The president also sent out an upbeat missive about the Capitol Hill meeting he had Tuesday with the Senate GOP, which occurred moments before Flake made his strongly-worded speech on the Senate floor.

'The meeting with Republican Senators yesterday, outside of Flake and Corker, was a love fest with standing ovations and great ideas for USA!' the president wrote.

Trump was still seething an hour later, when he sent a second tweet denigrating Flake and patting himself on the back for the standing ovation he claims he received, which Sen. John Kennedy of Louisiana confirmed.

'Jeff Flake, with an 18% approval rating in Arizona, said "a lot of my colleagues have spoken out." Really, they just gave me a standing O!' Trump said.

Meanwhile, Flake was engaging in a slash-and-burn TV tour Wednesday morning, going as far as to compare Trump to infamous Wisconsin Sen. Joe McCarthy.

As Trump departed for his day trip to Dallas Wednesday afternoon, he let loose on Flake again.

'Look, he was against me before he ever knew me,' Trump said. 'He wrote a book about me before I ever met him, before I ever knew his name.'

Trump called the book 'horrible' and said he thought Flake was a member of the opposing party when he first heard of him.

Flake's book, Conscience of a Conservative, came out in August of 2017, more than six months into Trump's presidency.

'His poll numbers in Arizona are so low that he couldn't win and I don't blame him for leaving,' Trump said, echoing his tweet from earlier in the day.

When a reporter asked about Flake's remarks, Trump answered, 'Well he's saying that, he's saying that because he has nothing else to say.'

On Tuesday, Flake told members of the Senate that he had 'children and grandchildren to answer to' and so would no longer be 'complicit or silent' when it came to a certain person sitting atop the executive branch.

'I decided I would be better able to represent the people of Arizona and to better serve my country and my conscience by freeing myself of the political consideration that consumed far too much bandwidth and would cause me to compromise far too many principles,' Flake said.

'To that end, I am announcing today that my service in the Senate will conclude at the end of my term in early January 2019,' Flake said.

The first response from the White House came from Press Secretary Sarah Huckabee Sanders, who called Flake's speech 'petty' and also suggested his departure from the Senate was probably for the best.

'I haven't spoken with him directly since the announcement by Sen. Flake,' Huckabee Sanders said of Trump. 'But I think that based on previous statements and certainly based on the lack of support that he has from the people of Arizona, it's probably a good move.'

Trump sang a similar tune Wednesday and suggested his brand would do better in the state sans Flake.

'I think I'll be boosted in Arizona because he's very unpopular,' Trump said, calling the Grand Canyon state a 'state that likes Donald Trump very much, as you, even you will admit,' the president added, scoffing at the press.

Flake holds a 30 per cent approval rating among all Arizona voters and a 37 per cent among just the state's Republicans, according to Morning Consult.

Flake had previewed his political escape to the Arizona Republic saying earlier Tuesday, 'there may not be a place for a Republican like me in the current Republican climate or the current Republican Party.'

He said he hadn't soured on the Senate, but rather the current condition of his Trump-led party.

'This spell will pass, but not by next year,' Flake said.

On the floor, Flake said he had risen to address 'a matter that has been very much on my mind at a moment when it seems that our democracy is more defined by our discord and dysfunction than our own values and principles.'

He began his speech by making the 'obvious point,' that elected political office isn't an indefinite career.

'We are not here to simply mark time,' he noted. 'Sustained incumbency is certainly not the point of seeking offices and there are time when we must risk our careers in favor of our principles.'

'Now is such a time,' he said.

Flake turned and expressed a number of regrets and implored that his colleagues not embrace what he called the 'new normal.'

Among the things that fit the definition: the coarseness of the present dialogue, the undermining of democratic ideals, personal attacks, threats against freedoms and institutions and the flagrant disregard for the truth.

'None of these appalling features of our current politics should ever be regarded as normal,' Flake said, adding a 'heaven help us,' if that becomes true.

Then he went after Trump – though never once uttered the president's name.

'We must stop pretending that the conduct of some in our executive branch are normal,' he said. 'They are not normal.'

'Reckless, outrageous and undignified behavior has been excuse as telling it like it is when it is actually reckless, outrageous and undignified,' Flake said. 'When such behavior emanates from the top of our government, it is something else. It is dangerous to a democracy.'

'Such behavior does not project strength because our strength comes from our values,' Flake continued. 'It, instead, projects a corruption of the spirit and weakness.'

The senator said lawmakers had fooled themselves long enough by thinking 'a pivot to governing is right around the corner.'

For months, first in the Republican primary last year, then during the general election and all through his first nine months in the White House, political watchers have wondered when President Trump would become more presidential. Flake predicted that time would be never.

The Republican looked to his fellow Republicans – though only Sens. John McCain, Bob Corker, both of whom have recently tussled with Trump, along with Sens. John Barrasso, Pat Roberts, Ben Sasse, Rand Paul and Jim Risch were in the room – and asked what would happen if the shoe was on the other foot.

Would his Republicans not speak out if a Democratic president was displaying this behavior?

Democrats were on hand too including Sens. Debbie Stabenow, Tim Kaine, Chris Coons, Jeff Merkeley, Jeanne Shaheen and Maggie Hassan.

'If I have been critical it is not because I relish criticizing the behavior of the president of the United States,' Flake said. 'If I have been critical, it is because I believe it is my obligation to do so, and as a matter of duty of conscience.'

While announcing that he would not run, Flake also pointed to the narrower and narrower path he would have had to weave through to win, saying his party's settled on a message 'more viscerally satisfying' that of 'anger and resentment.'

'To be clear, the anger and resentment that the people feel at the royal mess that we've created are justified,' he said. 'But anger and resentment are not the governing philosophy.'

He said populist politics often lead to 'mischaracterizing and misunderstanding our problems,' which in turn lead to 'the impulse to scapegoat and belittle,' which in turn lead to turning Americans into a 'fearful, backward-looking people.'

'In the case of the Republican Party, those things also threaten to turn us into a fearful, backward-looking minority party,' he said.

Turning his attention to the top of the party again, he used Trump's campaign motto against the president.

'We were not made great as a country by indulging in or even exalting our worst impulses, turning against ourselves, glorifying in the things that divide us and calling fake things true and true things fake,' he said. 'We did not become a beacon of freedom in the darkest corners of the world by flouting our institutions and failing to understand how hard won and vulnerable they are.'

Flake said he planned to spend the 14 months of his Senate career speaking out and ended his speech by quoting President Abraham Lincoln.

'A political career does not mean much if we are complicit in undermining these values,' Flake said.

Senate Majority Leader McConnell sat stone-faced through most of the speech, but applauded when it was over, then rose to salute one of his members.

'We’ve just heard a speech from a very fine man,' McConnell said.

McConnell had already had a trying day Tuesday, as Trump had restarted his spat with Corker hours before the Senate majority leader was hosting the president for lunch.

McConnell wanted the day's news to be about tax cuts.

But on Wednesday, Trump continued on with his feud with Corker too, though told reporters that he didn't think Corker's Foreign Relations Committee chair position should be stripped.

He also said he expected Corker, and Flake too, to vote for the tax package Republicans are trying to get through.

'I know them well enough, I don't know Flake that well, but I know Bob Corker, I think they'd really do it,' Trump said of giving the president a yes vote on the bill.