Bombshell US sanctions shake Mexico’s finance sector

Alfonso Romo, owner of Vector Casa de Bolsa, one of the three financial institutions sanctioned by the US Treasury this week for alleged ties to drug traffickers. Vector Casa de Bolsa, along with the other two firms, have denied the allegations. Image credit: Fotoarena / Alamy.

by Eduardo García.

Editor’s Note: Mr. García is Bloomberg’s former Mexico bureau chief. He is currently a senior advisor at Miranda Partners.

Around 1:00 pm Mexico City time, the US Treasury Department dropped a bombshell that shook the foundations of Mexico's financial system.

At that hour, three medium-sized financial institutions — well known in Mexican financial circles — were publicly accused of participating in money laundering operations linked to the financing of fentanyl production and distribution by Mexican drug cartels operating across the US-Mexico border.

The institutions named were CIBanco, Intercam Banco, and Vector Casa de Bolsa. The first two are based in Mexico City, while the third — a brokerage firm — operates out of Monterrey.

Never before had Mexican financial institutions of this size been accused — either in Mexico or the United States — of involvement in drug-related money laundering. In fact, these three are the first in the world to be sanctioned under a new US law: the FEND Off Fentanyl Act, passed in 2024. The legislation grants the Financial Crimes Enforcement Network (FinCEN), part of the US Treasury, the authority to designate foreign financial institutions as actors of primary money laundering concern based on "reasonable suspicion" of involvement in laundering funds linked to synthetic opioid trafficking.

Each case varies in scope and severity. CIBanco was singled out for the alleged complicity of an employee who reportedly helped the Gulf Cartel open an account to launder $10 million.

Intercam was accused of facilitating the acquisition of precursor chemicals for the Jalisco New Generation Cartel (CJNG) — a group designated as a foreign terrorist organization by the US government — through cash transfers totaling at least $1.9 million, made by individuals involved in cross-border drug trafficking.

Vector Casa de Bolsa, meanwhile, is accused of channeling $17 million through shell companies linked to Chinese chemical suppliers and criminal networks such as the Sinaloa Cartel and the Gulf Cartel. Some of these operations may also be tied to the case of Genaro García Luna, Mexico's former Secretary of Public Security under President Felipe Calderón, now imprisoned in the United States on charges of corruption and collusion with drug traffickers.

As a result of these findings, US authorities stated that once the designations are published in the Federal Register, all US financial institutions must cease all transactions with the sanctioned Mexican entities within 21 days.

This timeline highlights the Mexican banking system's deep dependence on cross-border financial ties, particularly with US intermediaries that provide crucial services such as correspondent banking, clearing, and international financing.

While the 21-day window might appear to give the sanctioned institutions — or the Mexican government — a chance to respond, clarify, or challenge the accusations, the likelihood of reversing the designations is slim. FinCEN is not legally required to consider external appeals or disclose the evidence supporting its conclusions. The regulation is a national security tool — not part of a conventional judicial process.

In fact, the issuance of these designations strongly suggests that FinCEN has already concluded a thorough internal investigation — likely in coordination with other agencies such as the Drug Enforcement Administration (DEA) and the Department of Justice — and considers the links between the institutions and drug financing to be substantiated.

While criticism of certain US federal agencies has intensified under President Donald J. Trump, particularly regarding politicization and lack of accountability, this action appears to be part of a broader bipartisan effort to confront the fentanyl crisis, which now ranks as a top national security concern in the US

Looking ahead, the targeted institutions may try to mitigate the damage by implementing aggressive compliance reforms or negotiating limited operational allowances. They might also redirect international activity toward banks in Europe or Latin America that are less sensitive to US regulatory pressure. However, there is no guarantee they will regain access to major international financial systems in the short term.

The responses from all three Mexican institutions were swift and forceful. Each denied any involvement in illicit activity and emphasized their long-standing compliance with national and international regulations for anti-money laundering (AML) and counter-terrorism financing (CTF).

For US authorities, however, these safeguards were insufficient. In their view, the institutions were — at the very least — indirect facilitators of illicit financial flows.

The Treasury's statement did not include documentary evidence to support its claims, and most of the underlying material remains classified. This lack of transparency will likely hinder the Mexican institutions' ability to mount a legal or reputational defense, since they may not know the specifics of the transactions in question.

The Mexican government also expressed surprise at the announcement. In an official statement, it noted that after receiving an initial warning months ago, it had requested further information from US authorities — without receiving a response until the designations were made public on Tuesday. The Ministry of Finance hinted that, despite frequent talk of bilateral cooperation in areas such as drug enforcement, there was no real coordination or information-sharing in this case.

The fallout goes beyond the named institutions. CIBanco, for example, is a key fiduciary operator in Mexico, involved in debt issuances, REITs (fibras), and CKDs (Capital Development Certificates). The reputational damage to these firms — and potentially to Mexico's financial system as a whole — could be deep and long-lasting.

Note: This article was originally published on Materia Gris. It is reprinted here in English with permission.