The U.S. State Department announced Friday night that Mexico would be deploying its National Guard troops throughout its country to help curb illegal immigration as part of the deal President Donald Trump boasted about after threatening Mexico with controversial tariffs.

However, according to a New York Times report on Saturday, Mexico had already agreed to deploy troops months before Trump threatened the country with the trade penalties. Mexican officials made the promise during secret talks with then-Homeland Security Secretary Kirstjen Nielsen in March, the Times reported, citing Mexican and U.S. officials familiar with the negotiations.

The difference between the promise made months ago and the one announced Friday night is the number of troops that will be deployed to various parts of Mexico, with the U.S.-Mexico border being a priority. According to the Times, the 5,400-troop deployment announced in Friday’s joint agreement is a much larger number than what Mexico had promised in March.

In late May, Trump threatened Mexico with a 5% tariff on any goods coming into the U.S. from the country, set to start on Monday, if Mexico did not agree to his terms on addressing the illegal border crossings by migrants from Central America.

Friday night, Trump called off the tariff and announced that the U.S. had reached a deal with Mexico that would “greatly reduce, or eliminate, illegal immigration.”