An emboldened Mexico hardened its opposition to President Donald Trump on Friday by saying it will retaliate if the United States imposes a border tax and that it can afford to lose financial aid that might be pulled to pay for a border wall.

Foreign Minister Luis Videgaray said Mexico could respond to any tax the United States unilaterally imposes on imports from its southern neighbor to finance the wall with levies on selected goods, aimed at U.S. regions most dependent on exports south of the border.

"Without a doubt, we have that possibility, and what we cannot do is remain with our arms crossed," Videgaray said in a radio interview. "The Mexican government would have to respond."