A top Defense Department official who internally raised concerns about freezing military aid to Ukraine has been asked by his national security superiors to resign and is stepping down.

Under Secretary of Defense for Policy at the Pentagon John Rood authored emails pushing for the aid to be released, according to CNN.

The departure was first reported by CNN and Bloomberg, and has since been confirmed to TPM by an administration official.

President Trump’s July order to halt the aid was the focus of the recent impeachment proceedings, which ended this month in a Senate acquittal vote. Rood is one of several administration officials caught up in the Ukraine mess who have since left the administration or were otherwise ousted from their positions.

Bloomberg News reported that Trump officials believed he was not executing the President’s agenda quickly enough because he did not fully agree with the policies.