MEXICO CITY — Under pressure from the Trump administration, Mexico’s foreign minister announced Friday that the country had reduced the flow of migrants heading to its northern border by more than 50 percent in the previous three months, an effort meant to keep damaging tariffs at bay.

Through the deployment of its newly formed National Guard, the Mexican government has aggressively targeted migrants traveling through its territory on their way to the United States. The results are stark: The number of migrants detained along the American-Mexico border dropped to 63,989 in August, from 146,266 at the end of May.

The announcement, from Foreign Minister Marcelo Ebrard, comes ahead of a meeting in Washington between the two nations. Tensions between the two countries flared this year, after President Trump threatened to impose tariffs on all Mexican imports unless the nation did more to stem the flow of migrants.

To avoid the tariffs, and threats of even more draconian tactics, the government of Mexico dispatched more than 20,000 police officers and Guard personnel to cover its southern border and the highways running north through the nation.