WASHINGTON (AFP) - President Donald Trump on Tuesday (April 16) vetoed a resolution from Congress directing him to end United States support for the Saudi-led war in Yemen, the second such move of his presidency.
The resolution was a harsh bipartisan rebuke to Mr Trump that took the historic step of curtailing a President's war-making powers - a step the President condemned in a statement announcing his veto.
"This resolution is an unnecessary, dangerous attempt to weaken my constitutional authorities, endangering the lives of American citizens and brave service members, both today and in the future," Mr Trump said.
Vetoing the measure is an "effective green light for the war strategy that has created the world's worst humanitarian crisis to continue", said International Rescue Committee president and chief executive officer David Miliband.
"This veto by President Trump is morally wrong and strategically wrongheaded. It sets back the hopes for respite for the Yemeni people and leaves the US upholding a failed strategy.
"Yemen is at a breaking point, with 10 million people on the brink of famine. There are as many as 100 civilian casualties a week and Yemenis are more likely to be killed at home than in any other structure."
The veto was the second of Mr Trump's presidency, after he overrode a congressional resolution that aimed to reverse the border emergency he declared in order to secure more funding for his wall between the US and Mexico in March.
Mr Trump argued that US support for the bloody war between the Saudi-backed Yemeni government and Iran-aligned Houthi rebels was necessary for a variety of reasons, "first and foremost" to "protect the safety of the more than 80,000 Americans who reside in certain coalition countries".
These countries "have been subject to Houthi attacks from Yemen", he said, referring to drone and missile strikes the Saudi-led coalition has either claimed were intercepted or denied altogether.
The President also said the resolution would "harm the foreign policy of the United States" and "harm our bilateral relationships".
And it would "negatively affect our ongoing efforts to prevent civilian casualties and prevent the spread of terrorist organisations such as Al-Qaeda in the Arabian Peninsula and ISIS, and embolden Iran's malign activities in Yemen", Mr Trump said, referring to two Sunni Muslim militant groups and his Shi'ite bete noire.
The resolution, which passed the US House of Representatives earlier this month and the Senate in March, was a historic milestone, as it was the first time in history that a measure invoking the 1973 War Powers Resolution reached the president's desk.
It was a reminder that Congress has the legal ability to compel the removal of US military forces, absent a formal declaration of war.
Democrats argued that US involvement in the Yemen conflict - through intelligence-sharing, logistical support, the sale of military equipment and now-discontinued aerial refuelling - is unconstitutional without congressional authority.
Critics of the intervention warn that Saudi forces are likely using US weapons to commit atrocities in the four-year war.
Some 10,000 people have been killed in Yemen over the past four years, according to the World Health Organisation, although rights groups say the toll could be five times higher.
Both the Saudi-led alliance and Houthi rebels have been accused of acts that could amount to war crimes, while the coalition has been blacklisted by the United Nations for killing and maiming children.