The Justice Department sought Monday to stop what they say would be “intrusive discovery” into President Donald Trump’s personal financial affairs, in a lawsuit brought by more than 200 Democratic members of Congress that raises separation-of-powers questions.

The government’s lawyers asked a federal appeals court in Washington, D.C., to throw out or freeze the lawsuit led by Sen. Richard Blumenthal, D-Conn., and Rep. Jerrold Nadler, D-N.Y., which alleges Trump violated the Foreign Emoluments Clause of the Constitution.

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A federal district court judge in April allowed the lawmakers to pursue the case, which seeks to delve into Trump’s vast business interests and determine whether he must get congressional approval before accepting payments or gifts from foreign governments.

Judge Emmet Sullivan also declined Trump’s motion to dismiss the case, and refused a DOJ request to allow the government to appeal that decision. And Sullivan announced he would set an expeditious schedule for discovery, which gives each side a chance to obtain evidence from the other side.

The Trump administration, in a rare type of petition Monday to the U.S. Court of Appeals for the District of Columbia Circuit, wrote that “litigating the claims would entail intrusive discovery into the President’s personal financial affairs on account of his federal office,” and that “the district court treated this case as a run-of-the-mill commercial dispute.”

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“In so ruling, the court ignored the unique separation-of-powers concerns posed by discovery in a case against the President in his official capacity,” the Justice Department wrote.

Lawmakers already sent 37 subpoenas in the case to third parties that require a response by July 29, the government said, and they have acknowledged that discovery may be directed at Trump.

The discovery “that the Members envision seeks to end-run the process of seeking information if there is a legitimate legislative interest, through congressional subpoena,” the government wrote.

The Justice Department added that the lawsuit “rests on a host of novel and flawed constitutional premises,” including whether legislators have the legal right to file such a lawsuit and the definition of what the term “emolument” means.

“The President has no other adequate means of obtaining relief,” the Trump administration wrote in the petition, noting that the U.S. Court of Appeals for the 4th Circuit has stopped proceedings in a similar Emoluments Clause lawsuit.

The House passed a Democrat-backed bill with provisions on the Emoluments Clause, and Sen. Elizabeth Warren, D-Mass., introduced a bill with similar language.