U.S.-bound migrant caravan in tense standoff at border between Mexico and Guatemala

A large caravan of Central Americans was preparing to cross the Guatemalan border into Mexico on Monday, posing a potential challenge to the Mexican government’s pledge to help the United States contain mass movements of migrants.

The migrants were massed on a bridge connecting the two countries early on Monday morning in what appeared to be a tense standoff with Mexican migration officials and soldiers.

U.S. President Donald Trump has threatened to punish Mexico and Central American countries economically if they fail to curb migrant flows, resulting in a series of agreements aimed at taking pressure off the . . .