Secretary of State Mike Pompeo has vowed to stop Democrats from 'bullying' State Department officials as they hand out subpoenas in their impeachment probe.

In a letter responding to a House subpoena demanding that he testify for Congress's impeachment investigation, Pompeo says that the requested time-frame given for employees to provide vast amounts of documents simply "isn't feasible." Those who have received subpoenas also need time to find and retain counsel to prepare for depositions, Pompeo said, adding that making depositions in the time frames offered won't be possible.

"...your letter provides a woefully inadequate opportunity for the Department and the requested witnesses to prepare. These individuals have retained, or may be retaining, private counsel, as is their constitutional right, and in the course of the Department's discussions with these individuals, several have indicated that they need more time both to retain and to consult with private counsel. In addition, State Department counsel must consult with these officials and their counsel, once retained, regarding the Department's legitimate interests in safeguarding potentially privileged and classified information."

Pompeo begins the letter by accusing Rep. Eliot Engel, Chairman of the House Committee on Foreign Affairs, of attempting to "bully, and treat improperly the distinguished professionals of the Department of State, including several career Foreign Service Officers, whom the Committee is now targeting." Pompeo vows to prevent any attempts to "intimidate, bully and treat improperly" any current or former State Department employees who get caught up in the investigation.

Finally, Pompeo said the subpoenas sent to five Department officials (including Pompeo himself) include requests for each individual to reproduce a "vast amount of documents." However, "these requests appear to duplicate the subpoena that was previously served on the Secretary of State. The requested records constitute the property of the Department of State and are subject to restrictions on the unauthorized disclosure of classified information and various Executive Branch privileges."

Read the full letter below:

JUST IN: Sec. Pompeo responds to subpoena, saying requested deposition dates "are not feasible;" asserts Democrats' request “can be understood only as an attempt to intimidate, bully, and treat improperly" State Dept. officials. https://t.co/2OeroCnGYE pic.twitter.com/Z6GYHgif19 — NBC News (@NBCNews) October 1, 2019

According to WSJ, Pompeo composed the letter after meeting with Italian President Sergio Mattarella in Rome on Tuesday. The former CIA chief has just begun a week-long trip to Italy and Greece.