It is not known what Trump plans to say to the 1,110 graduating cadets at the picturesque West Point campus.
Milley is known in the military as a charismatic leader who commanded troops during several tours in Iraq and Afghanistan.
Milley said his presence and the photographs compromised his commitment to a military divorced from politics.
Leaders from each of the services have now published memos to their force addressing Floyd's death.
Defense officials will testify on Capitol Hill as criticism mounts over their presence near the White House on Monday.
Troops leveled with Pentagon leaders on their issues in dealing with the COVID-19 crisis.
The chairman of the Joint Chiefs of Staff warned adversaries Thursday against "taking advantage" during the pandemic.
The Iranian missile attacks on Iraq were meant to kill U.S. troops, Joint Chiefs Chairman Gen. Mark Milley said Wednesday.
A "draft letter" suggesting a troop withdrawal was imminent circulated Monday, causing confusion.
More attacks from Iranian-backed militia groups may be possible, officials said.