Washington (CNN) The Trump administration has repeatedly insisted that its decision to kill Iranian General Qasem Soleimani was justified because he posed an "imminent threat" to American lives, but that phrase was notably absent in an official White House report sent to Congress that outlines the legal and policy rationale for conducting last month's strike.

A copy of the report -- released by House Foreign Affairs Committee Chairman Rep. Eliot Engel Friday -- is an unclassified version of what is called a 1264 notification, which the White House is required to send to Congress if it changes its view on the legal framework for using military force.

In this case, the notice not only outlines the administration's legal justification for killing Soleimani, but acknowledges that the White House expanded its interpretation of the 2002 Authorization for Use of Military Force to include military action against Iran.

"Iran's past and recent activities, coupled with intelligence at the time of the air strike, indicated that Iran's Qods Force posed a threat to the United States in Iraq, and the air strike against Soleimani was intended to protect United States personnel and deter future Iranian attack plans," the report reads.

It argues that the airstrike is consistent with longstanding interpretation of the President's authority under Article II of the Constitution and the 2002 AUMF, as the use of military force was "tailored narrowly to the Qods Force target's presence in Iraq and support to ... Iraqi militias that attacked US personnel."

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