Mexico will wait and see if U.S. President Donald Trump goes through with his threat to slap tariffs on its southern neighbor on Tuesday, the nation's president said on Monday, adding that Mexico has back-up plans in case the tariffs go into place.

Only a couple years ago, manufacturers were fighting for space to relocate their operations to Monterrey, an industrial city in Mexico’s northeast, as they sought to move closer to the US and its vast consumer market.

President Donald Trump says 25% tariffs on imports from Mexico and Canada will start Tuesday, sparking renewed fears of a North American trade war.