Donald Trump
Donald Trump Reuters

Tim Morrison, the top White House official on President Donald Trump's National Security Council for Europe, will be leaving his job, a source familiar with decision said on Wednesday, according to CNN.

The news comes on the eve of Morrison's testimony behind closed doors as part of the House impeachment inquiry.

Morrison's departure had been "planned for some time," the source stressed.

Morrison was recruited to join the NSC by former national security adviser John Bolton, and his departure has been expected since Bolton was fired in September. A number of Bolton's other allies at the NSC left around the time that he did, noted CNN.

Morrison is still finalizing his date for departure but the source says that he will still be a White House employee when he testifies Thursday.

Morrison has been at the NSC for about 15 months. He was initially the senior director of Weapons of Mass Destruction and Biodefense and took the Europe role over the summer.

The impeachment proceedings against Trump were launched by the Democrats in the wake of the President’s controversial conversation with Ukrainian President Volodymyr Zelensky in which he allegedly threatened to withhold aid to Ukraine unless its government investigated actions by former Vice President Joe Biden and his son, Hunter.

Last month the White House released the full, unredacted transcript of Trump's phone conversation with Zelensky.

“There’s a lot of talk about Biden’s son, that Biden stopped the prosecution and a lot of people want to find out about that so whatever you can do with the Attorney General would be great,” Trump said. Zelensky responded that he would appoint a new prosecutor general who would look into the matter of the company Hunter Biden had been on the board of.