By MEGAN JANETSKY

MEXICO CITY (AP) — The U.S. Treasury Department slapped sanctions Wednesday on three Mexico-based financial institutions it said were used to launder millions of dollars for cartels, in a move officials say would block certain money transfers between the sanctioned banks and U.S. banks.

The orders issued on the banks CIBanco and Intercam Banco, as well as brokerage Vector Casa de Bolsa, are part of an ongoing push by U.S. and Mexican authorities under pressure by U.S. President Donald Trump to crack down on Mexican cartels that traffic fentanyl.

The banks “have collectively played a long-standing and vital role in laundering millions of dollars on behalf of Mexico-based cartels and facilitating payments for the procurement of precursor chemicals needed to produce fentanyl,” Deputy Treasury Secretary Michael Faulkender told reporters on Wednesday.

Faulkender said the measures would “effectively cut off” the bank branches from doing business with U.S. financial institutions.

The three financial institutions did not immediately respond to requests for comment.

It was not immediately clear, however, how far-reaching the effects would actually be.

The Treasury orders said CIBanco and Intercam had each facilitated transfers to two U.S. financial institutions, and Vector had facilitated a transfer to one, but Treasury officials would not name which U.S. institutions were implicated nor provide more details.

Officials also did not rule out the possibility of foreign branches of the banks outside of Mexico being able to continue to do business with U.S. banks.

According to the Treasury orders, CIBanco helped facilitate money laundering for a number of cartels, including the Jalisco New Generation, Beltran Leyva and Gulf. Officials said the bank “facilitated procurement” of chemicals used to make fentanyl from China, by processing over $2.1 million in payments for the materials.

Vector was accused of facilitating money laundering for the Sinaloa and Gulf cartels, including $1 million in payments for fentanyl chemicals. The Treasury officials also said that Vector was used by the Sinaloa Cartel to send bribes to former Mexican Security Secretary Genaro García Luna, who was sentenced to more than 38 years in prison by a New York court in October for the charges. They estimated that transactions exceeded $40 million.

Intercam faced similar charges, and was accused of passing through transfers of $1.5 million in payments for chemicals used to produce fentanyl from China.

The orders were just the latest actions by the Trump administration, which has announced it was cracking down on Mexican cartels and fentanyl trafficking, despite movement of the drug along the border and overdoses within the U.S. already being on the decline.

This year, the administration also declared many of those cartels Foreign Terrorist Organizations and has sanctioned 31 people since Trump took office as part of the effort.

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