WASHINGTON — Even as they publicly insist President Donald Trump did nothing wrong during his call with Ukrainian president Volodymyr Zelenskiy, his allies are privately acknowledging more serious concerns about the ethical questions raised and the potential political fallout from it — especially over the involvement of Rudy Giuliani, Trump’s personal attorney.

Two Trump allies, one of whom is a former senior White House official, described a level of concern inside the White House that is far greater than Trump and his supporters have publicly acknowledged. The former official added that Giuliani’s role is particularly problematic legally because Giuliani has purely political and personal ties to Trump and has no official role with the U.S. government.

"It’s both better than I think many of us thought given what some of the speculation was, and also worse than many of us thought given what some of the speculation was," the official said. "The way in which it’s worse than people thought basically has to do with Giuliani."

Another Trump ally said they didn’t think Trump’s conduct as revealed by the memo is impeachable, but acknowledged the ethical questions raised. That ally specifically raised concerns about Trump mentioning Biden's name in the call, rather than just corruption more broadly.

“I wish he hadn’t said it — the Biden line,” that Trump ally said.

Still, another source close to the president pointed to what so far has been a solid wall of Republican support, even as House Democrats begin an official impeachment inquiry. No Republican lawmakers have joined Democrats in saying they support some type of action towards impeachment.

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Giuliani has tried to deflect criticism about his involvement in diplomatic issues by saying that he acted at the request of and in coordination with the State Department.

But while the State Department has acknowledged that one of its officials put Giuliani in touch with a top aide to the Ukrainian president at that aide’s request, the agency has otherwise tried to distance itself from Giuliani and his efforts in Ukraine. The State Department has described Giuliani as a private citizen who does not speak for the U.S. government.

And a senior Trump administration official said that Giuliani’s claim that the State Department “asked me” to look into Ukraine or initiated his interactions with Ukraine’s government is false.

The former senior White House official also said that Giuliani's claim that he worked through the State Department to coordinate his talks is highly questionable. The former official said that Giuliani should have “nothing to do with any of this stuff” and that his involvement in pursuing a corruption investigation “makes it inherently political rather than official law enforcement."

"It’s Giuliani who’s really dragged the president into something that’s a legal matter and a political matter and will be part of impeachment," the former official said. "What Giuliani did, there's no argument that it was a legitimate, government, law enforcement endeavor."

Yet Trump, who is often quick to abandon even his most loyal allies when it becomes politically expedient, was notably supportive of Giuliani when asked about him during a meeting with Ukraine’s president on Wednesday. He even praised Giuliani’s recent appearances on television.

Giuliani is known to provide Trump with informal political advice, and his assistance on an issue that could help the president politically has prompted speculation that he might be working for Trump’s re-election campaign. But a senior campaign official said Giuliani is not on the campaign’s payroll, and Federal Election Commission records do not show any payments by Trump’s campaign to Giuliani.