WEST PALM BEACH, Fla. — As the Russia investigation enters a crucial stage, President Trump is left without a veteran defense attorney at his side after two lawyers who were just hired to represent him dropped off on Sunday.

The announcement followed the resignation of John Dowd as Trump’s lead lawyer Thursday after their disagreements over the president’s desire for a more confrontational approach, including a face-to-face interview with investigators.

The turmoil on the president’s legal team, reflective of the chaos throughout his administration, now leaves unclear who will negotiate Trump’s potential interview with prosecutors from the office of special counsel Robert S. Mueller III.

Having proved himself to be an impulsive and outspoken client, prone to potentially damaging comments and tweets, Trump has struggled to hire top-shelf lawyers from the kind of marquee firm that typically relishes the prestige of representing a president.

The latest development came one week after Jay Sekulow, one of Trump’s other lawyers, said Joseph diGenova, a Republican and former U.S. attorney who has frequently criticized the Russia investigation in television appearances, was going to represent Trump. DiGenova’s wife, Victoria Toensing, who is also a former prosecutor, planned to join the team as well.

But Toensing has represented other people involved in the case, raising questions of conflicts of interest, and a subsequent review determined that Trump would need to look elsewhere for legal help.

“The president is disappointed that conflicts prevent Joe diGenova and Victoria Toensing from joining the president’s special counsel legal team,” Sekulow said in a text message Sunday. “However, those conflicts do not prevent them from assisting the president in other legal matters. The president looks forward to working with them.”

In a statement, DiGenova and Toensing said, “We thank the president for his confidence in us and we look forward to working with him on other matters.” DiGenova declined to comment further.

The announcement leaves a gaping hole in Trump’s team. Dowd, a defense attorney who had been serving as the president’s lead lawyer, had been handling negotiations over a potential interview with Mueller or his prosecutors. Although Sekulow still works for Trump, he is best known as an advocate for conservative religious causes, not as a defense attorney. Another lawyer, Ty Cobb, represents the White House in dealings with the special counsel’s office but doesn’t directly represent Trump.

Sekulow did not specify the potential conflicts for DiGenova and Toensing. Their firm has represented Sam Clovis, a former Trump campaign official, and Mark Corallo, who was a spokesman for Trump’s legal team.

Corallo said that on Monday he had waived any conflict claims should DiGenova and Toensing start working for Trump. “There were no conflicts as I could see them,” he told The Times on Friday.

Corallo resigned from his spokesman’s job in July, soon after the president helped draft a misleading statement about a meeting his eldest son held at Trump Tower in June 2016 with a Russian lawyer offering “dirt” on Hillary Clinton. That statement said that Donald Trump Jr. and the lawyer discussed a program for adopting Russian children and that their encounter was unrelated to the campaign.

That was revealed to be false, but Trump Jr. said no incriminating information was provided at the meeting. Also in attendance were Paul Manafort, then the campaign manager, and Jared Kushner, the president’s son-in-law and advisor.

The absence of legal talent behind the president stands in contrast to the special counsel’s bench. Mueller has employed a team of seasoned prosecutors, including money-laundering experts, to investigate whether any Trump associates assisted Russian efforts to interfere in the 2016 election. He’s also examining whether the president obstructed justice by trying to impede the investigation.

Trump has denied any collusion between his campaign and Russia and has condemned the investigation as a “witch hunt.”

The announcement about DiGenova and Toensing came just after Trump, in tweets Sunday morning from his Mar-a-Lago estate in Florida, dismissed reports about the travails of his legal team as “fake news.”

He wrote in one, “Many lawyers and top law firms want to represent me in the Russia case...don’t believe the Fake News narrative that it is hard to find a lawyer who wants to take this on. Fame & fortune will NEVER be turned down by a lawyer, though some are conflicted.”

Trump seemed to suggest that it could be some time before a new lawyer would be in place, writing, “Problem is that a new lawyer or law firm will take months to get up to speed (if for no other reason than they can bill more), which is unfair to our great country — and I am very happy with my existing team.”

Trump has professed satisfaction with his lawyers before, prior to previous shake-ups. After the New York Times reported that he met with Emmet Flood, who represented President Clinton during the impeachment process, Trump said the reporters “purposely wrote a false story stating that I am unhappy with my legal team and am going to add another lawyer to help out. Wrong.”

Eleven days later, DiGenova was announced as a new lawyer for the president and Dowd quit.

The moves on Trump’s legal team parallel the shake-up roiling the top ranks of his administration. Six major figures, including his secretary of State, national security advisor and chief economic advisor, have been pushed out or announced their resignations in the last three weeks. More could be following.

On ABC’s “This Week” on Sunday, Trump confidant Christopher Ruddy said the president told him Saturday that he is “perplexed” by reports of chaos at the White House. But Ruddy added, “He’s expecting to make one or two major changes to his government very soon.”

chris.megerian@latimes.com