The merging of Iranian-backed terrorist groups with transnational criminal organizations in Latin America has become a mounting national security threat to the United States, according to several U.S. and foreign officials.

South America's tri-border region, where Argentina, Brazil, and Paraguay converge, is of particular concern given the longstanding presence of Hezbollah militants, who operate as money launderers for drug cartels. The collaboration generates tens of millions of dollars for the Iranian terror proxy with a cut set aside for drug lords.

The 10th Parliamentary Intelligence-Security Forum brought together Trump administration officials, U.S. lawmakers, and 150 foreign delegates from over 50 countries on Thursday to discuss joint efforts to combat global terrorist financing.

Rep. Robert Pittenger (R., N.C.), chairman of the congressional taskforce on terrorism and unconventional warfare, who organized the event, warned of an uptick in Hezbollah’s activities in the tri-border area and said he fears the Islamic State or affiliated groups will establish funding channels in the region.

"Hezbollah has been there for a couple of decades, but you now have an expansion of it," Pittenger told the Washington Free Beacon. "The tri-border area is fairly open, it needs more oversight, particularly with the flow of cars, boats, etcetera involved in narcotics and illicit financing."

Pittenger in November met with South American government officials in Buenos Aires to discuss greater collaboration between the United States and its regional partners to thwart terrorist financing operations. The talks, involving representatives from Argentina, Brazil, Colombia, Ecuador, and Paraguay, among others, touched on the importance of multilateral intelligence sharing and cooperation between the public and private sector to confront the threat.

Mariano Federici, president of Argentina's Financial Intelligence Unit, said on Thursday the United States and Argentina are in the process of building "a strong strategic partnership for the protection of our mutual security and the integrity of our financial systems and economies."

"The risks stemming from the tri-border area are a priority concern to our government," Federici said in Washington, citing the devastating 1992 and 1994 bombings thought to be carried out by Iranian-backed militants in Buenos Aires.

He said a recent fact-finding trip conducted by U.S. and Argentinian officials confirmed ongoing money laundering operations in the tri-border area in which large volumes of cash were transferred to Hezbollah-controlled territory in Lebanon.

U.S. officials have long warned of terrorist groups taking root in Latin America.

During his time as chief of U.S. Southern Command, retired Gen. John Kelly often expressed concern about the nexus of terrorist groups and illicit narcotic and smuggling networks in the region. His successor, U.S. Navy Adm. Kurt Tidd, last year echoed similar worry of the potential for Islamist radicalization and narcoterrorism.

Pittenger said the United States must work with regional partners to deploy capabilities that better track the movement of money and drugs while simultaneously helping to ensure judicial independence so courts can better prosecute narcoterrorist networks.