NEW YORK >> A 2021 federal raid on Rudy Giuliani’s home and office was spurred by suspicions that the former New York City mayor had sought the removal of the U.S. ambassador to Ukraine partly because of the prospect of a financial reward from a Ukrainian official, according to documents made public Tuesday.

The documents provide new detail on the since-concluded investigation into Giuliani’s involvement with Ukrainian figures in the run up to the 2020 presidential election. Giuliani, a longtime ally of former President Donald Trump, was not charged with a crime as a result of the inquiry.

In a search warrant application, federal agents seeking to seize Giuliani’s cell phones, laptop and other electronic devices raised the possibility that he and three other people could be charged with acting as unregistered foreign agents.

The documents, unsealed at the request of The New York Times and dating to the weeks before the raids, confirmed past news reports that federal prosecutors in Manhattan were examining whether Giuliani had gotten anything of value from Ukrainian figures in return for lobbying the Trump administration to fire then-U.S. Ambassador to Ukraine Marie Yovanovitch.

The search warrant application said that Giuliani had been “incentivized” to lobby for the ambassador’s removal in two ways.

First, it said, Yuriy Lutsenko, the prosecutor general in Ukraine who wanted the ambassador fired, had offered to hire Giuliani to lobby the Trump administration for help recovering Ukrainian assets he believed had been misappropriated by a U.S. investment firm.

“As discussed below, Giuliani was interested in being engaged to do that work, and proposed a retainer with a $200,000 upfront payment. Thus, it appears that Giuliani took steps to cause the firing of the Ambassador to prove to what he could achieve in order to, among other things, secure the legal representation,” the search warrant said.

Secondly, the application said, Giuliani wanted Lutsenko’s help launching an investigation that might hurt Democratic rival Joe Biden.

Both Lutsenko and Giuliani have previously denied there was anything inappropriate about their interactions.

Prosecutors noted that the proposed $200,000 retainer was never paid. Giuliani has said he also never lobbied the Trump administration on Lutsenko’s behalf.

A message seeking comment was left Tuesday with Giuliani’s spokesperson.

In November 2022, federal prosecutors revealed in a letter to a federal judge that Giuliani would not face criminal charges over his interactions with Ukrainian figures before the 2020 presidential election.

“Based on information currently available to the Government, criminal charges are not forthcoming,” they wrote. They said the grand jury probe that led to the seizure of Giuliani’s electronic devices had concluded.

Giuliani tweeted soon afterward that it was a “COMPLETE & TOTAL VINDICATION.”

The contours of the investigation were broadly known even before its conclusion, but details of what evidence prosecutors were acting on when they sought to search Giuliani had not been revealed.

The Times wrote to the judge in October seeking copies of the search warrants, warrant applications, supporting affidavits and other documents.

Giuliani consented to releasing the search warrant documents, according to U.S. District Judge J. Paul Oetken’s order unsealing them.

The documents contained numerous redactions, with many names and other identifying information blacked out. Trump’s name appeared in the documents more than two-dozen times, mainly pertaining to Giuliani’s alleged lobbying efforts. There was no suggestion that investigators suspected Trump of wrongdoing.

In an affidavit filed with Manhattan federal magistrates to secure search warrants, investigators wrote it appeared Giuliani had been aware of FARA registration requirements for some time and had publicly stated that he believed he was not required to register because he has never lobbied the U.S. government on behalf of his clients.

The disclosure of the search warrant documents comes amid a tangle of recent and ongoing legal challenges for the Republican ex-mayor.

Giuliani was indicted in August in Georgia on charges he acted as Trump’s chief co-conspirator in a plot to subvert Biden’s victory. He was also described as a co-conspirator but not charged in special counsel Jack Smith’s federal election interference case against Trump.

Last week, a jury in Washington, D.C. ordered Giuliani to pay $148 million in damages to two former Georgia election workers who sued him for defamation over lies he spread about them in the wake of Trump’s 2020 election loss.

The former workers, Wandrea “Shaye” Moss and her mother Ruby Freeman, sued Giuliani again on Monday, alleging he continued to defame them during the trial.

The April 2021 raid on Giuliani’s Manhattan apartment and office was seen at the time as a major escalation of the Justice Department’s yearslong investigation of his dealings in Ukraine.

At the same time, agents also served a warrant for a phone belonging to Washington lawyer Victoria Toensing, a former federal prosecutor and close ally of Giuliani and Trump. Her law firm said she was informed she was not a target of the investigation. She was not charged.

Giuliani accused federal authorities at the time of “running rough shod over the constitutional rights of anyone involved in, or legally defending” Trump.

Giuliani was central to the then-president’s efforts to press Ukraine for an investigation into Biden and his son, Hunter.

Giuliani also sought to undermine Yovanovitch, who was pushed out on Trump’s orders. He met several times with a Ukrainian lawmaker who released edited recordings of Biden in an effort to smear him before the election.

Hunter Biden was charged by U.S. authorities in September with federal gun crimes and is scheduled to be arraigned next month on tax charges.

The federal Foreign Agents Registration Act requires people who lobby on behalf of a foreign government or entity to register with the Justice Department.

The once-obscure law, aimed at improving transparency, has received a burst of attention in recent years — particularly during Special Counsel Robert Mueller’s probe of foreign election interference, which revealed an array of foreign influence operations in the U.S.