Forget tariffs. Another tool of economic statecraft is far better suited to the problem of illegally manufactured fentanyl.

The U.S. Treasury said on Wednesday it had extended a deadline to September 4 for a prohibition on certain transactions involving three Mexican financial institutions hit by sanctions last month over alleged money laundering linked to fentanyl trafficking.

The trust deficit that often clouds U.S.-Mexico cooperation — rooted in concerns over corruption, impunity and sovereignty — must be addressed head-on.

President Donald Trump posted letters to the leaders of Mexico and the European Union, saying they had not done enough to head off the new tariffs.