(NewsNation) — The White House is responding to a spate of subpoenas and interview requests issued by House Republicans targeting President Joe Biden’s family members and aides, describing it as “harassment to the President to score political points.”

In the four-page letter obtained by NewsNation, special counsel to the president Richard Sauber challenged the validity of the GOP-led impeachment inquiry into President Biden.

“You appear so determined to impeach the President that you have misrepresented the facts, ignored the overwhelming evidence disproving your claims, and repeatedly shifted the rationale for your ‘inquiry,’” Sauber wrote to House Oversight Chair James Comer, R-Ky., and House Judiciary Chair Jim Jordan, R-Ohio.

Sauber’s letter comes after Comer subpoenaed former White House counsel Dana Remus and requested transcribed interviews with four White House employees as part of the investigation into Biden’s alleged mishandling of classified documents. Comer previously subpoenaed President Biden’s son, Hunter Biden, and the president’s brother, James Biden, connected to their business dealings.

House Republicans have alleged Biden family members engaged in “influence peddling” and that Biden himself profited from the foreign business ventures of his son, Hunter, while serving as vice president from 2009 to 2017.

However, House Republicans have not produced any evidence of wrongdoing by Joe Biden.

Sauber also called on the Republican chairmen to withdraw their subpoenas and demands for interviews, arguing the impeachment inquiry lacks “constitutional legitimacy” since it was launched without a formal vote on the House floor.

“You also claim the mantle of an ‘impeachment inquiry’ knowing full well that the Constitution requires that the full House authorize an impeachment inquiry before a committee may utilize compulsory process pursuant to the impeachment power—a step the Republican House Majority has so far refused to take,” Sauber wrote.

Comer responded Friday in a statement vowing to press ahead with his demands for interviews with White House staff members.

“If President Biden has nothing to hide, then he should make his current and former staff available to testify before Congress about his mishandling of classified documents,” Comer said in a statement. “Our investigation has unearthed new facts that contradict the White House’s and President Biden’s personal attorney’s narrative of the events.”