WASHINGTON (AP) — House Democrats took their first concrete steps in the impeachment investigation of President Donald Trump on Friday, issuing subpoenas demanding documents from Secretary of State Mike Pompeo and scheduling legal depositions for other State Department officials.

At the end of a stormy week of revelation and recrimination, House Speaker Nancy Pelosi framed the impeachment inquiry as a somber moment for a divided nation.

“This is no cause for any joy,” she said on MSNBC.

At the White House, a senior administration official confirmed a key detail from the unidentified CIA whistleblower who has accused Trump of abusing the power of his office. Trump, for his part, insisted anew that his actions and words have been “perfect” and the whistleblower’s complaint might well be the work of “a partisan operative.”

The White House acknowledged that a record of the Trump phone call that is now at the center of the impeachment inquiry had been sealed away in a highly classified system at the direction of Trump’s National Security Council lawyers.

Separately, Trump adviser Kellyanne Conway told reporters that the whistleblower “has protection under the law,” something Trump himself had appeared to question earlier in the day. He suggested then that his accuser “isn’t a whistleblower at all.”

Still at issue is why the rough transcript of Trump’s July 25 phone call with Ukraine’s president was put on “lock down,” in the words of the whistleblower. The CIA officer said that diverting the record in an unusual way was evidence that “White House officials understood the gravity of what had transpired” in the conversation.

The whistleblower complaint alleges that Trump used his office to “solicit interference from a foreign country” to help himself in next year’s U.S. election. In the phone call, days after ordering a freeze to some military assistance for Ukraine, Trump prodded new Ukrainian President Volodymyr Zelenskiy to dig for potentially damaging material on Democratic rival Joe Biden and volunteered the assistance of both his personal attorney, Rudy Giuliani, and U.S. Attorney General William Barr.

Pelosi refused to set a deadline for the probe but promised to act “expeditiously.” The House intelligence committee could draw members back to Washington next week.

Pelosi said she was praying for the president, adding, “I would say to Democrats and Republicans: We have to put country before party.”

At the White House, it was a senior administration official who acknowledged that the rough transcript of Trump’s conversation with Ukraine’s Zelenskiy had been moved to a highly classified system maintained by the National Security Council. The official was granted anonymity Friday to discuss sensitive matters.

White House attorneys had been made aware of concerns about Trump’s comments on the call even before the whistleblower sent his allegations to the intelligence community’s inspector general. Those allegations, made in mid-August, were released Thursday under heavy pressure from House Democrats.

All the while, Trump was keeping up his full-bore attack on the whistleblower and the unnamed “White House officials” cited in the complaint, drawing a warning from Pelosi against retaliation.

Late Thursday, Trump denounced people who might have talked to the whistleblower as “close to a spy” and suggested they engaged in treason, an act punishable by death. Then on Friday, he said the person was “sounding more and more like the so-called Whistleblower isn’t a Whistleblower at all.”

He also alleged without evidence that information in the complaint has been “proved to be so inaccurate.”

Pelosi told MSNBC, “I’m concerned about some of the president’s comments about the whistleblower.”

She said the House panels conducting the impeachment probe will make sure there’s no retaliation against people who provided information in the case. On Thursday, House Democratic chairmen called Trump’s comments “witness intimidation” and suggested efforts by him to interfere with the potential witness could be unlawful.

Rep. Joaquin Castro, D-Texas, a member of the intelligence committee, said the president calling whistleblowers spies is “obscene … just grotesque.”