The State Department inspector general is expected to deliver an “urgent” briefing to staffers on House and Senate committees Wednesday afternoon about their requests for documents and testimony on the Ukraine investigation, according to a report.​

​Steve Linick will meet with staff from the House and Senate Appropriations, Oversight, Foreign Affairs and Intelligence committees at a secure location on Capitol Hill, ABC News reported.

​The development comes as Secretary of State Mike Pompeo ​sent a letter to the heads of three House panels on Tuesday, accusing them of trying to “bully” and “intimidate” State Department officials by asking for depositions and documents about Ukraine.

​”​Let me be clear: I will not tolerate such tactics, and I will use all means at my disposal to prevent and expose any attempts to intimidate the dedicated professionals whom I am proud to lead and serve alongside at the Department of State,” ​Pompeo told them in a tweet.

​The chairs — Rep. Eliot Engel of Foreign Affairs, Rep. Adam Schiff of Intelligence and Rep. Elijah Cummings of Oversight — responded by saying Pompeo would be a “fact witness” if he took part in a phone call between President Trump and Ukrainian leader Volodymyr Zelensky that prompted the impeachment inquiry.

Pompeo on Wednesday admitted that he was on the July 25 call.

During the call, Trump asked Zelensky to work with his personal lawyer Rudy Giuliani and Attorney General William Barr to investigate Democratic presidential candidate Joe Biden and his son Hunter.

Giuliani said the State Department asked him to reach out to Ukraine and Pompeo knew about it.

“I did not do this on my own. I did it at the request of the State Department and I have all of the text messages to prove it. And I also have a thank you from them from doing a good job,” ​the former mayor told CBS’ “Face the Nation”​ on Sunday.​ “When I talked to the secretary last week, he said he was aware of it.”