A comprehensive and damning United Nations report released Tuesday said the U.S., France, and Britain may be guilty of complicity in war crimes for providing the Saudi Arabia-led coalition in its war on Yemen with logistical support and weapons.

"Five years into the conflict, violations against Yemeni civilians continue unabated, with total disregard for the plight of the people and a lack of international action to hold parties to the conflict accountable," said Kamel Jendoubi, chairperson of the Group of Experts on Yemen, which was created by the U.N. Human Rights Council.

"We must use Congress's power of the purse to block every nickel of taxpayer money from going to assist the Saudi dictatorship as it bombs and starves civilians in Yemen."

—Sen. Bernie Sanders

The 274-page report (pdf) said the U.S., France, and Britain may have failed to live up to their obligations under international law by continuing to provide weaponry, training intelligence, and logistical support for a Saudi-led coalition that is guilty of bombing hospitals, homes, a school bus, and other civilian targets during its years-long assault on Yemen.

"The legality of arms transfers by France, the United Kingdom, the United States, and other states remains questionable," the report states, "and is the subject of various domestic court proceedings."

In a statement, Jendoubi condemned the nations involved in the Saudi-led war on Yemen for refusing to investigate and punish human rights violations.

"This endemic impunity—for violations and abuses by all parties to the conflict—cannot be tolerated anymore," said Jendoubi. "Impartial and independent inquiries must be empowered to hold accountable those who disrespect the rights of the Yemeni people. The international community must stop turning a blind eye to these violations and the intolerable humanitarian situation."

The report, which is the product of a two-year investigation, comes days after the Saudi-led coalition killed more than 100 people in airstrikes on a Yemeni detention center. The International Committee of the Red Cross (ICRC) said the attack may have amounted to a war crime.

Following the attack, a bipartisan group of lawmakers including Sens. Bernie Sanders and Elizabeth Warren launched a new effort to end U.S. complicity in the Saudi-led assault on Yemen, which has killed tens of thousands of people and caused the world's worst humanitarian crisis.

The Washington Post reported late Monday that the lawmakers are working to bar the U.S. government from providing logistical support for the Saudi-led coalition's air raids.

The group called on the Senate to not remove an amendment to the annual defense policy legislation that would prohibit the U.S. from cooperating with Saudi airstrikes.

In a letter to top Republicans and Democrats on the House and Senate Armed Services Committees, which are set to hash out differences between the two chambers' defense policy bills, the group of lawmakers said "inclusion of this amendment would ensure that our men and women in uniform are not involved in a war which has never been authorized by Congress, and continues to undermine rather than advance U.S. national security interests."

The letter, first obtained by the Post, was signed by Sens. Warren (D-Mass.), Sanders (I-Vt.), Rand Paul (R-Ky.), Mike Lee (R-Utah), and dozens of others.

As Common Dreams reported in April, President Donald Trump vetoed a stand-alone War Powers resolution that would have ended U.S. military support for the Saudi-led assault on Yemen.

Sanders said in a statement to the Post on Monday that Congress has a responsibility to continue asserting its constitutional authority to bring U.S. complicity in the war on Yemen to an end.

"Now," said Sanders, "we must use Congress's power of the purse to block every nickel of taxpayer money from going to assist the Saudi dictatorship as it bombs and starves civilians in Yemen."