The FBI's Peter Strzok requested in the summer of 2017 that he retain his security clearance after being added to special counsel Robert Mueller's team, according to emails published by conservative watchdog group Judicial Watch on Tuesday.

Strzok has become the center of a heated debate in Washington about the integrity of the Justice Department and FBI over text messages he sent to a colleague that display a bias against President Trump. Obtained through a Freedom of Information Act lawsuit in partially redacted form, an email he sent on July 13, 2017 to FBI officials asked that he keep all the authorities he held as a deputy assistant director in the counterintelligence division.

[WATCH: Peter Strzok forced to read his own anti-Trump texts]

"Broadly, I need to be able to act at least in the capacity of my old CD DAD job – approve NSLs [national security letters], conduct [redacted] declassify information, [redacted] agent travel, requisitions, etc. Of those, the most problematic and one of the most essential is declassification authority," Strzok said.

In reply, FBI's assistant director of the Counterintelligence Division, William Priestap, said Strzok would maintain his authorities.

"In answer to your initial question, while assigned to the Special Counsel’s office, you will retain your CD DAD authorities, to include declassification authority," Priestap said. "Since you will take your non-transferrable declassification authority with you, CD will work to obtain another declassification authority slot for the DAD who is chosen to replace you."

He added: "Assuming the 7th floor approves, you will remain on CD’s books as a fourth (floating) DAD. When you move on from your DAD position, your DAD slot will revert back to HRD."

Also included in the 14 pages of documents obtained by Judicial Watch are what appear to be FBI colleagues congratulating Strzok on his new role, with one person emailing: "Congratulations on your new assignment! Good things happen to good people! As I've told you before, you're one of a few that I'll follow to the moon and back! :)." The name of that sender was redacted.

Strzok was grilled publicly by the two committees earlier this month, following a Department of Justice inspector general report that said he had a “biased state of mind” while working on the FBI’s investigation into Hillary Clinton’s private email server, and later when working on the Russia investigation.

Republicans have zeroed in on the texts between Strzok and former FBI lawyer Lisa Page, who were on both FBI investigations while simultaneously having an extramarital affair. The messages contain a slew of anti-Trump sentiments, which Republicans and the president alike have said show bias atop the Justice Department and FBI. Mueller removed Strzok after the text messages were made public, but the latter defended the removal because of the “appearance” of bias, not the bias itself.

“These new emails show anti-Trump FBI official Peter Strzok’s ‘assignment’ gave the Mueller Special Counsel operation special authorities to target President Trump,” said Judicial Watch President Tom Fitton said of the new batch of emails obtain by his group. “We know Strzok can’t be trusted and the Special Counsel should tell us if Strzok abused his special authorities to target President Trump.”

Attorney General Jeff Sessions said during a radio interview in June that in the midst of an internal disciplinary review, “Mr. Strzok, as I understand, has lost his security clearance." However, while testifying before Congress this month, Strzok said he had top secret clearance with some [Sensitive Compartmented Information] compartments." A DOJ official told the Daily Caller that his access was a brief measure. “Strzok was given a limited clearance in prep for today’s hearing which will end when this is over," the official said.

