State Department officials told a House Foreign Affairs subcommittee hearing that U.S. cooperation with Mexico on counternarcotics has intensified, producing extraditions, seizures and new joint mechanisms to hold partners accountable.

Katherine Duholme, principal deputy assistant secretary for the Bureau of Western Hemisphere Affairs, and Chris Landberg, senior bureau official at the Bureau of International Narcotics and Law Enforcement Affairs (INL), said the two governments established a security implementation group that meets monthly to track commitments. "As partners, we can accomplish more together," Duholme said during opening remarks, calling the U.S.–Mexico relationship "one of our country's most complex, strategic, and consequential." Landberg added that Mexico "extradited or transferred a 133 major cartel figures to [the] United States this year to stand trial." (Landberg)

Witnesses described a mix of operational actions: Mexico deployed what Duholme called Operativo Frontera Norte (about 10,000 National Guard personnel) and reported arrests, firearms seizures and kilogram‑level drug seizures on border operations; INL described dismantling synthetic‑drug labs, major precursor seizures, and targeted law enforcement training. Landberg said INL‑supported units helped seize precursor chemicals and supported undercover purchases that led to indictments. He also said the ATF eTrace firearms‑tracking platform has been expanded to 25 of Mexico's 32 states and that INL is discussing deployment in the remainder.

Several members cited past oversight problems. Rep. Shreve pointed to a 2023 GAO report that criticized earlier assistance for lacking measurable benchmarks and monitoring; Landberg said the administration reviewed foreign assistance programs, ended some that did not meet U.S. national security priorities, reorganized INL, and is pushing for clearer metrics through tools such as "devresults." Shreve also noted that a Cross‑Border Accountability Act provision passed in the NDAA and will impose additional fraud risk assessments.

Lawmakers pressed witnesses on where the U.S. will focus next. Duholme and Landberg emphasized illicit finance as a key target, noting that Treasury and OFAC actions prompted Mexican authorities to close three banks identified as laundering concerns. "That sent shock waves through the Mexican banking industry," Landberg said. Both witnesses urged more resources and faster criminal‑justice prosecutions in Mexico to turn arrests and seizures into convictions.

The exchange also touched on international cooperation: officials said a November agreement between President Trump and President Xi Jinping increased controls on precursor exports from China, and they said the U.S. is monitoring how effective those controls prove to be.

Committee members requested follow‑up information and pressed for more transparency about strikes and interagency coordination. The subcommittee indicated it will seek written answers and additional briefings.

The hearing did not include formal votes. Members requested written responses and reserved time for additional rounds of questioning.