Reuters first reported the department's move Friday.
President Obama and the GOP-controlled Congress are in the midst of a feud over the pipeline: the House has already passed legislation granting a permit to TransCanada to build the project, which would transport heavy crude from Hardisty, Alberta, to oil refineries on the U.S. Gulf Coast.
Obama has threatened to veto the bill, which is expected to pass the Senate next week.
Once the eight agencies submit their comments, Secretary of State John F. Kerry will begin an "open-ended determination process."
After Kerry makes a final decision, the other agencies will have 14 days to review the determination and object if they disagree with it. Obama can weigh in at any time, though he's obligated to make the final decision if an agency formally objects to State's final determination.