An assistant U.S. attorney for the Southern District of New York said Monday that a new indictment was "likely" in the criminal campaign-finance case against two associates of Rudy Giuliani.

Assistant U.S. Attorney Douglas Zolkind—answering a question posed by U.S. District Judge J. Paul Oetken of the Southern District of New York—confirmed that the investigation into defendants Lev Parnas and Igor Fruman remained ongoing, but declined to comment any further in open court.

"We think a superseding indictment is likely, but no decision has been made," Zolkind said. "It's something we're continuing to evaluate."

Attorneys for Parnas and Fruman, meanwhile, said they had not yet seen much of the evidence that had been collected through "voluminous discovery" in the case, which accuses both men, and two other associates, of engaging in a scheme to violate U.S. campaign-finance laws.

According to a four-count indictment, Parnas and Fruman allegedly conspired to funnel foreign money to candidates for state and federal office in order to buy influence among lawmakers and state governments. Both men are former clients of Giuliani, the former New York City mayor who has come under fire recently for his role in alleged efforts by President Donald Trump to have the Ukrainian government interfere in the 2020 U.S. election.

Giuliani has not been charged with any wrongdoing.

Congressional impeachment investigators however are scrutinizing the former New York City mayor's dealings in Ukraine, and, according to reporting of the New York Times, prosecutors in the Southern District have been probing his connections with Parnas and Fruman.

Co-defendants Andrey Kukushkin and David Correia were also charged with one count each of conspiracy in the case.

Zolkind said the government had seized 12 electronic devices from Parnas, including five iPhones, two iPads, a MacBook, a hard drive and two other phones either during his arrest in October or during a later search of his home. Among the devices taken from Fruman were two iPhones, a satellite phone, three thumb drives and a cell phone, Zolkind said.

Prosecutors have also subpoenaed phone, bank and internet records and carried out multiple search warrants for email accounts and electronic devices.

Defense attorneys for the four men, however, decried delays in accessing evidence that the government had collected against their clients, and floated measure to expedite production.

"We have no sense of this case," said attorney Gerald B. Lefcourt, who represents Kukushkin.

"We  have no idea how much time its going to take to get through all this stuff," he said.

Zolkind responded that the U.S. Attorney's Office was in the process of scanning paper documents and planned to return them to defense counsel as soon as possible. He also said the government had requested passwords for electronic devices, which would help the process move along more swiftly.

Oetken declined to grant defense requests to speed up production, but noted that the bulk of evidence would be returned to the defendants within 60 days. He set the conference in the case for Feb. 3.

Of the four defendants, only Parnas was present Monday in the courtroom. His attorney, Joseph Bondy, reiterated that his client was planning to comply with the House Judiciary Committee, which had subpoenaed Parnas for documents that were currently in the government's possession.

Zolkind said prosecutors would not object to an order that certain documents be turned over to Congress, and Oetken said he expected to grant the request.

Fruman, Correia and Kukushkin all waived their appearances and were excused from attending Monday's hearing.

Fruman is represented by Todd Blanche of Cadwalader, Wickersham & Taft, and Correia is represented by William Joseph Harrington of Goodwin Procter.

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