"This force is deploying for the purpose of protecting U.S. citizens and property, if necessary, and is equipped for combat," the letter read. "This force will remain in Iraq until the security situation becomes such that it is no longer needed."
According to a statement from White House Press Secretary Jay Carney, the troops will relocate staff from the U.S. Embassy in Baghdad.
The State Department announced Sunday that it would move some personnel from Baghdad to other consulates in Iraq and neighboring Jordan. Carney's statement reiterated the State Department's assertions that the "majority" of Embassy staff would stay in place.
Obama's letter comes after Secretary of State John Kerry said Monday that he "wouldn't rule out" talks with Iran about the crisis in Iraq, where Sunni militants are thought to be pushing toward Baghdad.
Here's Obama's full letter to Congress:
Starting on June 15, 2014, up to approximately 275 U.S. Armed Forces personnel are deploying to Iraq to provide support and security for U.S. personnel and the U.S. Embassy in Baghdad.
This force is deploying for the purpose of protecting U.S. citizens and property, if necessary, and is equipped for combat.
This force will remain in Iraq until the security situation becomes such that it is no longer needed.
This action has been directed consistent with my responsibility to protect U.S. citizens both at home and abroad, and in furtherance of U.S. national security and foreign policy interests, pursuant to my constitutional authority to conduct U.S. foreign relations and as Commander in Chief and Chief Executive.
I am providing this report as part of my efforts to keep the Congress fully informed, consistent with the War Powers Resolution (Public Law 93-148). I appreciate the support of the Congress in these actions.