The dollar weakened against the Mexican peso on Wednesday after President Donald Trump introduced his plans for tightening security along the U.S.'s southern border. The dollar USDMXN, +1.29% fell 1.6% to 21.14 pesos, compared with 21.51 pesos late Tuesday in New York. Trump signed two executive orders pertaining to immigration: one authorizing his promised border wall and another providing more resources to immigration authorities inside the U.S. In his remarks, Trump emphasized that a strong Mexican economy is good for the U.S., and that he would maintain a productive relationship with the U.S.'s southern neighbor. The Mexican currency is on track for its largest daily gain against the dollar since Nov. 15.