Donald Trump’s Justice Department this week blocked two FBI agents from testifying before Congress about the Russian interference in the 2016 presidential election.

In response, Sen. Chuck Grassley (R-IA), chairman of the Senate Judiciary Committee, is drafting subpoenas for the two FBI agents DOJ blocked from testifying before the committee, ABC’s Ali Rogin reports.

.@ChuckGrassley says he is "in the process" of drafting subpoenas for the 2 FBI agents whom the DOJ has blocked from talking to Judiciary — Ali Rogin (@AliABCNews) September 14, 2017

The news comes after CNN reported Wednesday the DOJ is refusing to cooperate with Senate investigators probing Donald Trump’s decision to fire former FBI Director James Comey. The two agents, Carl Ghattas and James Rybicki, could reportedly provide first-hand testimony about the president’s communications with Comey leading up to his ouster.

In a letter to the Senate Judiciary Committee, the Department of Justice declined to make Ghattas and Rybicki available for transcribed interviews before the panel, citing “the appointment of Robert S. Mueller III” to investigate Russian interference in the 2016 presidential election.

“Under these circumstances and consistent with the Department’s long-standing policy regarding the confidentiality and sensitivity of information relating to pending matters, the Department cannot make Mr. Ghattas nor Mr. Rybicki available for transcribed interviews at this time,” Acting Assistant Attorney General Samuel Ramer wrote in the letter.

“The Senate committee has yet to receive cooperation from DOJ and the special counsel’s office in scheduling those interviews voluntarily,” a spokesman for Grassley told the news network.

He added: “Both the judiciary committee and the special counsel are engaged in important investigations, and we are committed to being as cooperative with Mueller’s office as we can, which is why we’ve been in ongoing communication with Mueller’s team.”