WASHINGTON – The former White House expert on Russia and three State Department officials are scheduled for House depositions this week as part of the fourth week of the impeachment investigation of President Donald Trump.

The three House committees conducting the depositions – Foreign Affairs, Intelligence and Oversight and Reform – set several deadlines for subpoenas this week for documents from Trump's personal lawyer, Rudy Giuliani, the Pentagon and the White House Office of Management and Budget.

Trump, who has called the inquiry an unfair partisan "witch hunt," scheduled a rally for Thursday in Dallas.

House Speaker Nancy Pelosi, D-Calif., declared an impeachment inquiry Sept. 24. The investigation is focused on a phone call Trump made July 25 to Ukrainian President Volodymyr Zelensky, in which he urged his counterpart to investigate former Vice President Joe Biden, a Democratic political rival. At the time, the White House held up congressionally approved military aid for Ukraine.

The impeachment inquiry is looking at whether Trump abused his office for his own political gain and whether he used the military aid to pressure Ukraine to gather dirt on Biden and his son Hunter, who served on the board of an energy company in Ukraine while his father was vice president. No evidence has surfaced of any wrongdoing by Biden or his son.

Trump described the call with Zelensky as “perfect” and insisted there was no "quid pro quo" in which he demanded a Biden investigation in exchange for the military aid. The White House notified Pelosi on Oct. 8 that the administration would refuse to cooperate with the House investigation.

Here's what to expect this week:

MONDAY: Former White House expert

The former National Security Council senior director for Europe and Russia, Fiona Hill, was subpoenaed to testify Monday despite White House opposition to the investigation. Hill’s lawyer, Lee Wolosky, said she was subpoenaed and would “comply and answer questions” from the three committees leading the part of the investigation that focuses on Trump’s dealings with Ukraine.

NBC News reported that Hill was expected to tell the three committees that Giuliani and the U.S. ambassador to the European Union, Gordon Sondland, led a shadow policy on Ukraine that circumvented the National Security Council.

TUESDAY: Subpoena deadline

Giuliani was subpoenaed for documents and given a deadline of Tuesday. The three committees said they sought documents because Giuliani appeared to have "pressed the Ukrainian government to pursue two politically motivated investigations.” Giuliani has publicly acknowledged his efforts to press Ukrainian government officials to investigate Biden, a leading candidate for the 2020 Democratic presidential nomination.

Giuliani hasn't said whether he will comply with the subpoena. "I have received a subpoena signed only by Democrat Chairs who have prejudged this case," he tweeted Sept. 30. "It raises significant issues concerning legitimacy and constitutional and legal issues including ... attorney client and other privileges. It will be given appropriate consideration."

Tuesday is also the deadline for subpoenas to the Pentagon and the White House Office of Management and Budget for documents detailing why military aid to Ukraine was frozen. Despite the White House proclamation against cooperating, Defense Secretary Mark Esper said he will comply with the subpoena.

“The enclosed subpoena demands documents that are necessary for the committees to examine this sequence of these events and the reasons behind the White House’s decision to withhold critical military assistance to Ukraine that was appropriated by Congress to counter Russian aggression," said the letter from the three chairmen: Rep. Eliot Engel, D-N.Y., at Foreign Affairs; Rep. Adam Schiff, D-Calif., at Intelligence; and Rep. Elijah Cummings, D-Md., at Oversight and Reform.

House Democrats requested documents from Vice President Mike Pence relating to the inquiry, setting a deadline of Tuesday, but Pence might not comply.

"Given the scope, it does not appear to be a serious request but just another attempt by the Do Nothing Democrats to call attention to their partisan impeachment," spokeswoman Katie Waldman said in a statement.

Also Tuesday, George Kent, the deputy assistant secretary of state, has a private deposition scheduled with the three committees. Giuliani accused Kent in May during an interview with a Ukrainian news site of working with liberal philanthropist George Soros to find “dirty information” on Trump campaign officials. Kent previously served as deputy chief of mission in Kyiv and spent years working on anti-corruption efforts across Europe.

WEDNESDAY: McKinley hearing

P. Michael McKinley, a former senior advisor to Secretary of State Mike Pomeo, is scheduled to appear before lawmakers in a closed session.

McKinley resigned from his post just last week after a career that spanned decades and posts as U.S. ambassador for countries including Brazil and Afghanistan. The timing of his departure raised questions and the Washington Post reported that his resignation came amid low morale within the State Department and worries that Pompeo was not supporting those wrapped up in the controversy over Ukraine, allegations Pompeo denied in an interview with The Tennessean.

"I protect every single State Department employee," he said. "It’s one of the reasons that we asked the House of Representatives to stop their abusive prosecutions where they won’t let State Department lawyers sit with our employees. That’s not fair."

Also on Wednesday is a document deadline for two of Giuliani's clients, Ukrainian-born business partners Lev Parnas and Igor Fruman. The two Florida businessmen showered Republican campaign committees with contributions and introduced Giuliani to a prosecutor in Ukraine. Parnas and Fruman were arrested Oct. 9 and charged with U.S. campaign finance violations.

THURSDAY: Sondland testimony

Sondland is expected to testify privately under subpoena Thursday after refusing to appear voluntarily Oct. 8 under direction from the State Department. Trump tweeted that he didn’t want Sondland appearing before a “kangaroo court.”

Texts between Sondland and other diplomats revealed concerns that the administration was linking the military aid to a Ukrainian investigation of Biden, but Sondland said there was no specific demand for action in exchange for funding. A text from William Taylor, the top U.S. diplomat in Ukraine, called it “crazy to withhold security assistance” to Ukraine in exchange for “help with a political campaign.” Sondland responded that the assertion was “incorrect” about Trump’s intentions. “The President has been crystal clear no quid pro quo’s of any kind,” he said in a text message. The Washington Post reported Oct. 12 that Sondland called Trump between Taylor's text and his own reply and that the message came from the president.

Ulrich Brechbuhl, the State Department counselor, is scheduled for a deposition Thursday with the three committees. Brechbuhl is a longtime friend of Secretary of State Mike Pompeo after both graduated from the U.S. Military Academy at West Point and served together in Germany. Brechbuhl and Pompeo were business partners at Thayer Aerospace, a Kansas defense company. Brechbuhl was among those listening to the call July 25, according to a whistleblower’s complaint.

Trump’s rally in Dallas follows two last week, in Minneapolis and Lake Charles, Louisiana. In Minneapolis, Trump railed against what he called the “insane impeachment witch hunt” and accused Democrats in “the wretched Washington swamp” of trying to nullify the 2016 election by removing him. Trump told the crowd in Lake Charles that Pelosi hates America and that the investigation is "illegal, invalid and unconstitutional."

Pelosi slammed Trump for his “potty mouth” and said the Minneapolis speech was “beyond disgraceful.”

FRIDAY: Cooper testimony

Deputy Assistant Secretary of Defense Laura Cooper is expected to appear Friday before lawmakers in a closed-door session.

Cooper is a career Defense official, who joined the department in 2001, is responsible for policy regarding a number of countries, including Russia and Ukraine, topics that lawmakers will be eager to ask about. Cooper could have knowledge about the delay of military aid for Ukraine.

Energy Secretary Rick Perry also faces a subpoena deadline of Friday from the three committees for documents about Ukraine. Trump said he made the phone call July 25 at Perry’s suggestion. The committees cited reports that Perry pressed Zelensky to fire board members of the state-owned energy company Naftogaz, championing their replacement with Parnas and Fruman.

Contributing: Christal Hayes

More on the impeachment investigation of President Donald Trump:

All of the people who have been subpoenaed in House Democrats' impeachment inquiry

Nancy Pelosi announces formal impeachment inquiry into Donald Trump over Ukraine scandal