FILE - In this May 23, 2018, file photo, Paul Manafort, President Donald Trump's former campaign chairman, leaves the Federal District Court after a hearing, in Washington. Special counsel Robert Mueller is accusing Manafort of lying to federal investigators in the Russia probe in breach of his plea agreement. Prosecutors say in a new court filing that after Manafort agreed to truthfully cooperate with the investigation, he “committed federal crimes” by lying about “a variety of subject matters.” (AP Photo/Jose Luis Magana, File)

WASHINGTON — A lawyer for Paul Manafort, the president’s onetime campaign chairman, repeatedly briefed President Trump’s lawyers on his client’s discussions with federal investigators after Manafort agreed to cooperate with the special counsel, according to one of Trump’s lawyers and two other people familiar with the conversations.

The arrangement was highly unusual and inflamed tensions with Mueller’s office when prosecutors discovered it after Manafort began cooperating two months ago, the people said. Some legal specialists speculated it was a bid by Manafort for a presidential pardon even as he worked with the special counsel, Robert S. Mueller III, in hopes of a lighter sentence.

Rudolph W. Giuliani, one of the president’s personal lawyers, acknowledged the arrangement on Tuesday and defended it as a source of valuable insights into the special counsel’s inquiry and where it was headed. Such information could help shape a legal defense strategy, and it also appeared to give Trump and his legal advisers ammunition in their public relations effort against the special counsel’s office. For example, Giuliani said, Manafort’s lawyer Kevin M. Downing told him that prosecutors hammered away at whether the president knew about the June 2016 Trump Tower meeting where Russians promised to deliver damaging information on Hillary Clinton to his eldest son, Donald Trump Jr. The president has long denied knowing about the meeting in advance. “He wants Manafort to incriminate Trump,” Giuliani declared of Mueller.

While Downing’s discussions with the president’s team violated no laws, they helped contribute to a deteriorating relationship between lawyers for Manafort and Mueller’s prosecutors, who accused Manafort of holding out on them despite his pledge to assist them in any matter they deemed relevant, according to the people. That conflict spilled into public view on Monday when the prosecutors declared that Manafort had breached his plea deal by lying to them about several subjects.

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