On Saturday afternoon, Trump sent a letter to member of Congress, informing them about the US missile strike against the Syrian Air Force base, and stating that the US will take additional action to further the country’s national interests, the White House said Saturday.

In the letter Trump explained his decision to launch an attack on the Shayrat Airbase in Syria, as one meant to avert a “humanitarian catastrophe” and explained the targeting of the airfield because US "intelligence indicates that Syrian military forces operating from this airfield were responsible for the chemical weapons attack on Syrian civilians in southern Idlib Province, Syria, that occurred on April 4,” Trump wrote in the letter.

"I directed this action in order to degrade the Syrian military's ability to conduct further chemical weapons attacks and to dissuade the Syrian regime from using or proliferating chemical weapons, thereby promoting the stability of the region and averting a worsening of the region's current humanitarian catastrophe."

Most notable is Trump's claim that he acted “in the vital national security and foreign policy interests of the United States,” and his promise that the US "will take additional action, as necessary and appropriate, to further its important national interests."

Full text of Trump's letter to the Speaker of the House and the President of the Senate:

April 8. 2017 Dear Mr. Speaker: (Dear Mr. President:) At approximately 8:40 p.m. Eastern Daylight Time on April 6, 2017, at my direction, United States military forces in the Mediterranean Sea, operating beyond the territorial sea of any state, struck the Shayrat military airfield in Syria. United States intelligence indicates that Syrian military forces operating from this airfield were responsible for the chemical weapons attack on Syrian civilians in southern Idlib Province, Syria, that occurred on April 4. I directed this action in order to degrade the Syrian military's ability to conduct further chemical weapons attacks and to dissuade the Syrian regime from using or proliferating chemical weapons, thereby promoting the stability of the region and averting a worsening of the region's current humanitarian catastrophe. I acted in the vital national security and foreign policy interests of the United States, pursuant to my constitutional authority to conduct foreign relations and as Commander in Chief and Chief Executive. The United States will take additional action, as necessary and appropriate, to further its important national interests. 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 this action. Sincerely, DONALD J. TRUMP

Trump's letter to Congress about Syria: "I acted in the vital national security and foreign policy interests of the United States." pic.twitter.com/6tydMb95K0 — Philip Crowther (@PhilipinDC) April 8, 2017

It was not immediately clear if Congress will demand that it pre-clears any future air strikes against Syria, should Trump continue his military campaign.

As a reminder, the he US strike came before the UN or the OPCW, the chemical weapons watchdog, could investigate the incident and the allegation the Assad was behind the attack as the media claimed . Washington rushed to accuse the Syrian government for the suspected chemical attack. In 2003 it rushed to invade Iraq because it "had weapons of mass destruction."