CNN —

Manhattan District Attorney Alvin Bragg is suing House Judiciary Chairman Jim Jordan, over what the lawsuit filed Tuesday describes as a “transparent campaign to intimidate and attack” his office’s case against former President Donald Trump.

The suit injects more legal drama into Bragg’s investigation of Trump, which has been dogged for weeks by accusations from Republicans that the prosecutor’s pursuit of the former president was purely political, with the claims being central to Jordan’s own probe.

Bragg is seeking to block a subpoena for testimony from Mark Pomerantz, a former senior prosecutor in his office, as well as other demands for “confidential documents and testimony from the district attorney himself as well as his current and former employees and officials.” The 50-page suit is asking a federal court to give emergency and permanent relief that would block enforcement of Jordan’s subpoena for Pomerantz to testify on April 20. Pomerantz told Jordan last month that, per instructions from Bragg’s office, he does not plan to cooperate with the subpoena.

US District Judge Mary Kay Vyskocil denied Bragg’s request for emergency relief later Tuesday, though the court could still block the subpoena through other forms of relief. She also set a hearing on the matter for April 19.

“In sum, Congress lacks any valid legislative purpose to engage in a free-ranging campaign of harassment in retaliation for the District Attorney’s investigation and prosecution of Mr. Trump under the laws of New York,” the lawsuit, filed in the US District Court for the Southern District of New York, states.

“That campaign is a direct threat to federalism and the sovereign interests of the State of New York. This Court should enjoin the subpoena and put an end to this constitutionally destructive fishing expedition.”

CNN has reached out to Jordan for comment on the lawsuit.

The congressman criticized the lawsuit in a tweet on Tuesday, writing: “First, they indict a president for no crime. Then, they sue to block congressional oversight when we ask questions about the federal funds they say they used to do it.”

In the suit, Bragg knocks Jordan’s assertion that $5,000 in federal funds used in relation to his office’s investigation into Trump that led to the indictment gives the committee grounds to investigate.