"It's more important than ever to take every measure possible to prevent illicit flows," the UNODC's executive director, Ghada Waly, told a U.N. Security Council meeting, saying arms trafficking and gang activity were feeding off each other.

A recent UNODC report found that most illegal firearms seized in Haiti came from the United States, notably Florida, Arizona, Georgia, Texas and California.

The report found a prevalence of handguns manufactured by Taurus, Glock, Beretta, and Smith & Wesson; the latter three are defendants in a Caribbean-backed Mexican landmark lawsuit seeking to hold gun makers accountable for trafficking outside U.S. borders.

None of the gun manufacturers immediately responded to a request for comment.

The report said traffickers likely worked with sanctioned Haitians to smuggle weapons to gangs, particularly 400 Mawozo and 5 Segond, which the report said were acting as brokers using firearms distribution to further cement their power.

After the Dominican Republic shut its border with Haiti, smugglers were turning to more remote routes including clandestine airstrips, the report said.

U.S. Deputy U.N. Ambassador Robert Wood said "more must be done" to hold gangs and their backers accountable. He did not specifically mention the U.S. connection.

The meeting comes a day ahead of a Kenyan hearing set to determine whether Kenya's proposed leadership of a U.N.-ratified force to help outgunned Haitian police fight gangs is legal. No date has been set for deployment, which Haiti requested in October 2022.

Countries have been wary of volunteering troops after previous U.N. missions left behind a cholera epidemic that killed close to 10,000 people and widespread allegations of sexual abuse by peacekeepers.

"The U.N. has made mistakes in Haiti. This is an opportunity to get it right," Human Rights Watch Executive Director Tirana Hassan told the meeting, adding that Haitians the organization interviewed said they were wary but needed urgent support.

Hassan said some 300,000 people were now internally displaced, many whose homes were burned down, and called on neighboring nations to stop deporting hundreds of thousands of migrants back to Haiti.

Jose de la Gasca, the U.N.'s ambassador from Ecuador, which is facing its own internal conflict against armed gangs, called for justice and reparations regarding the allegations against peacekeepers of the U.N.'s 2004-2017 mission to Haiti.

(Reporting by Sarah Morland; Additional reporting by Michelle Nichols; Editing by Leslie Adler)

By Sarah Morland