Mexico instituted restrictions on nonessential travel starting Sunday at its border with Guatemala as the U.S. grapples with an influx of Central American migrants attempting to enter the country.

Under the new regulations, Mexico is only allowing essential travel across the border it shares with Guatemala, with the Mexican government saying the limitations are focused on reducing the spread of COVID-19, The Associated Press reported.  

But the restrictions come at the same time that Mexico is under pressure to reduce the levels of migration heading toward the U.S. Besides its previous agreement with the U.S. regulating non-essential travel, Mexico has not instituted health restrictions on those entering its country. 

Dozens of immigration agents were positioned at the Mexican banks of the Suchiate river, requested documentation for those crossing the border and ordered several to turn back. 

In previous years, Mexican officials faced crowds of migrants trying to cross the river, but this time there were a reduced number of migrants at the river, according to the AP. 

Mexicos National Migration Institute committed last week to curbing the number of illegal migrants at its border with Guatemala, through using drones and militarized police, as the U.S. has seen a surge in family and unaccompanied minors trying to cross the border.  

But the AP noted that many of these migrants are thought to be traveling with smugglers to numerous crossing points along Mexicos borders with Guatemala and Belize.

Mexico estimates that 4,180 accompanied and unaccompanied minors have illegally crossed Guatemalas border into Mexico through March 18 this year. 

On Saturday, CBS News reported that the number of unaccompanied migrant children in U.S. custody reached beyond 15,000 children.  

Mexican officials announced their discovery of hundreds of Central American migrants in three tractor-trailers by the countrys border with Guatemala on Thursday, including 114 unaccompanied minors.

Mexico has reported more than 2.1 million COVID-19 cases, leading to more than 197,000 deaths, according to data from Johns Hopkins University.