The Justice Department has been reviewing the unmasking of U.S. officials as part of its broader examination of the origins of the Trump-Russia investigation and is now taking a look at related files that acting Director of National Intelligence Ric Grenell delivered to the DOJ last week, Fox News has learned.

As Fox News previously reported, Grenell made the decision to declassify information about Obama administration officials who were involved in the “unmasking” of former National Security Adviser Michael Flynn — whose calls with the former Russian ambassador during the presidential transition were picked up in surveillance and later leaked.

GRENELL DECLASSIFIES NAMES OF OBAMA OFFICIALS WHO 'UNMASKED' FLYNN

“To the extent that this information is related to any open investigation we will be taking a close look at it," a DOJ official said.

However, tensions appear to be emerging between the ODNI and DOJ over who should make the call on whether to actually release the documents shared by Grenell.

The DOJ official told Fox News that the Justice Department currently has no plans to release that list of names.

Fox News is told the ODNI is the owner of that information, and if they want to release it they can do so. "That's their call," a source said.

Acting Director of National Intelligence Ric Grenell enters the Justice Department in Washington on May 7. (Jake Gibson, Fox News)

The Justice Department was consulted on the issue because the intelligence community does not necessarily have total authority over its own information when it comes to releasing it to the public. Any U.S. government intelligence that is released lawfully to the American public is supposed to first undergo review either by the DOJ or by the president. It is illegal to release unmasked intelligence information for political gain.

DOJ'S FLYNN FILINGS RENEW FOCUS ON MYSTERIOUS SUSAN RICE EMAIL DURING TRANSITION

But a source told Fox News that once the information has been declassified by Grenell, he, as the acting director of National Intelligence, has the authority to release it.

The ODNI's office has not yet responded to a request for comment on this issue.

The Justice Department’s stance comes after Grenell decided to declassify information about Obama administration officials who were behind the “unmasking” of Flynn.

The unmasking concerns events between the November 2016 election and Inauguration Day 2017, Fox News is told.

Unmasking occurs after U.S. citizens' conversations are incidentally picked up in conversations with foreign officials who are being monitored by the intelligence community. The U.S. citizens' identities are supposed to be protected if their participation is incidental and no wrongdoing is suspected. However, officials can determine the U.S. citizens' names through a process that is supposed to safeguard their rights.

Meanwhile, Fox News confirmed that a new round of documents is expected in the wake of a document dump last week that renewed focus on the Russia investigation and specifically the treatment of Flynn.

Another source familiar with the intelligence told Fox News that Grenell is moving to declassify several pieces of intelligence in stages, with this one being part of it. Asked if former President Barack Obama’s name is on the list of officials involving in unmasking Flynn, the source would not say, but stressed that the list would make waves.

The Wall Street Journal, which reported on the looming release overnight, cited a senior government official who called Grenell’s move unprecedented, as it came just days after the Justice Department dropped its case against Flynn.

Officials in the Obama administration have acknowledged that they moved to unmask some Americans in intelligence reports, but insisted that their reasons were legitimate. Those officials include Obama National Security Adviser Susan Rice, former ambassador to the United Nations Samantha Power and former deputy national security adviser Benjamin Rhodes.

The move coincided with the department's stunning reversal in the Flynn case, which was previously seen as special prosecutor Robert Mueller's signature case from the Russian collusion investigation.

The decision to drop the case was made even though prosecutors, for the past three years, have maintained that Flynn lied to the FBI in a January 2017 interview about his conversations with the Russian ambassador. Flynn pleaded guilty to this, but later sought to withdraw the plea.

Recent documents released in the case included handwritten notes in which FBI officials questioned the purpose of interviewing Flynn. "What is our goal?" one of the notes read. "Truth/Admission or to get him to lie, so we can prosecute him or get him fired?”

In court documents filed last week, the Justice Department said that after reviewing newly disclosed information and other materials, it agreed with Flynn’s lawyers that his Jan. 24, 2017, interview with the FBI should never have taken place because he had not had inappropriate contacts with Russians. The interview, the department said, was “conducted without any legitimate investigative basis.”

Fox News' Ed Henry and Gillian Turner contributed to this report.