CNN  — 

The day after the Trump administration blocked a diplomat from attending his scheduled deposition, Secretary of State Mike Pompeo said his department and the White House would fulfill their legal and constitutional requirements in the House impeachment inquiry.

“I’ve made clear, I think the White House has made very clear, we will ensure that we do everything that we’re required to do by the law and the Constitution. Every time,” he told “PBS NewsHour” on Wednesday.

But Pompeo’s comments, coming amid a week of silence from the rest of State Department on all matters related to the impeachment inquiry, offered little clarity as to whether the department will allow its diplomats to cooperate with the probe.

In a separate interview Wednesday on “America This Week with Eric Bolling,” Pompeo suggested the response to the impeachment inquiry would be guided by the administration’s lawyers and that the State Department would take its cues from the White House.

“The White House made a decision yesterday: They issued an extended letter talking about this process that the House is engaged in, making clear that the White House’s view is that this is not a legitimate impeachment proceeding,” he said. “We’ll take our guidance from them in terms of how we respond, but I’ve also made clear to my team here at the State Department: We have a mission. We still have a mission in Ukraine. We still have objectives.”

On Tuesday, US Ambassador to the European Union Gordon Sondland was instructed by the State Department not to testify to Congress as scheduled, according to his attorney Robert Luskin. In light of the move, the House Intelligence Committee, in coordination with the House Foreign Affairs and Oversight committees, issued a subpoena on Tuesday evening for testimony and documents from Sondland.

“In light of Secretary Pompeo’s direct intervention to block your appearance before our committees, we are left with no choice but to compel your appearance at a deposition pursuant to the enclosed subpoena,” Foreign Affairs Chairman Eliot Engel of New York, Oversight Chairman Elijah Cummings of Maryland and Intelligence Chairman Adam Schiff of California, all Democrats, wrote in a letter to Sondland.

Former US Ambassador to Ukraine Marie Yovanovitch is scheduled to testify on Friday. It is unclear whether she will be permitted to do so. Of the five diplomats who were scheduled to testify by the House, only former Special Representative for Ukraine Kurt Volker has been deposed. He resigned from the State Department days before his congressional appearance. The State Department has not responded to repeated inquiries on any of the scheduled depositions.

In a letter to Engel and again in a news conference in Athens, Greece, on Saturday, the secretary of state had suggested the House was harassing and bullying the diplomats by seeking testimony and documents from them.

“Sadly, there have been congressional inquiries that have harassed and abused State Department employees by contacting them directly and seeking to have them provide documents – documents that belong to the State Department, that are official US government records – and ask them to do so without – saying, ‘Hey, don’t bother calling the State Department lawyers; just talk to us directly.’ That’s harassment, and I’ll never let that happen to my team,” he said Saturday.

Last Friday, Pompeo failed to meet a congressional subpoena deadline to produce Ukraine-related documents.

On Saturday, he told reporters that the State Department had sent a letter to Congress on Friday night with its “initial response” to the document request. The department has not divulged the contents of that letter.

“We’ll obviously do all the things we are required to do by law,” Pompeo said during the news conference in Athens.

“I was a member of Congress once; Article I has a certain set of powers, and Article II has an obligation to make sure that we protect officials at the State Department,” the secretary of state said. “We’ll work through this process.

“I remember once when I was on that side and we were looking for documents, I remember precisely how long it took for those documents to come across. So – and we’re going to beat that. We’re going to be more responsive than the Obama administration was in the years preceded this particular Congress,” he added, referencing his time as a member of the House Select Committee on Benghazi, which investigated the terror attacks that killed four Americans in September 2012 in Benghazi, Libya, and the role of former Secretary of State Hillary Clinton.

Former State Department official and Special Assistant to the Vice President for Europe and Eurasia Molly Montgomery told CNN, “It’s frankly disgraceful that the department would block its own officials from being deposed for the impeachment inquiry when they’ve said they want to do so.”

“It’s particularly ironic coming from Secretary Pompeo, who himself led efforts to get a lot of State Department officials called before Congress on dubious charges,” she said.

Many former and current State Department officials have expressed doubt, fear and outrage at the way the agency has been ensnared in and has responded to the unfolding Ukraine controversy.

Retired Ambassador Ronald Neumann on Tuesday called the department’s blocking of congressional testimony by diplomats “a very questionable action,” adding that he doesn’t understand “the basis on which the State Department rejects congressional oversight, which has always been part of the constitution.”

CNN’s Kylie Atwood, Michael Conte, Jeremy Herb, Zachary Cohen, Katelyn Polantz and Manu Raju contributed to this report.