WASHINGTON (AP) — The acting director of national intelligence is balking at demands from the House intelligence committee to turn over a secret whistleblower complaint or appear at a hearing this week, escalating a weeklong standoff.

Committee Chairman Adam Schiff subpoenaed Joseph Maguire last week, saying he was withholding a whistleblower complaint from Congress and questioning whether he had been directed to do so by the White House or the attorney general. Schiff did not divulge the subject of the whistleblower complaint, but said the committee has been told that the intelligence community's inspector general determined it to be credible and a matter of "urgent concern."

Schiff said if the complaint was not turned over, Maguire would be required to appear at a Thursday hearing.

In a letter Tuesday, the general counsel for the Office of the Director of National Intelligence, Jason Klitenic, wrote that such a hearing would be "premature" and that Maguire was not available to testify this week. Klitenic wrote that the agency is protecting the whistleblower and argued the allegation does not meet the definition of "urgent concern." He said the complaint "concerned conduct from someone outside the intelligence community and did not relate to 'intelligence activity' under the DNI's supervision."

Klitenic said the office was still willing to negotiate with the committee.

Schiff said Tuesday evening that the committee must "move quickly" on the subject and that the committee's position is clear.

"The acting DNI can either provide the complaint as required under the law, or he will be required to come before the committee to tell the public why he is not following the clear letter of the law, including whether the White House or the attorney general are directing him to do so," Schiff said. "He has yet to provide the complaint in response to the committee's subpoena, so I expect him to appear on Thursday, under subpoena if necessary."

Schiff said last week that Maguire is required to share the complaint with Congress, and "this raises serious concerns about whether White House, Department of Justice or other executive branch officials are trying to prevent a legitimate whistleblower complaint from reaching its intended recipient, the Congress, in order to cover up serious misconduct."

He added that he was concerned that administration officials "are engaged in an unlawful effort to protect" President Donald Trump.