The Brazilian real and the Mexican peso both strengthened around 1 percent.
The peso slipped 0.3 percent after touching a three-week peak earlier in the day.
The peso rose more than 2 percent after Trump said in a speech a strong Mexican economy was good for the United States and that he wanted to see it flourish.
The peso had strengthened on Friday after Trump refrained from specifically mentioning Mexico in his inauguration speech.
The Mexican peso strengthened 1 percent but still hovered near an all-time low touched earlier this month.
The peso hit a record low in January and traded close to that low just above 22 per dollar on Thursday.
The peso dropped nearly 2 percent after Trump's choice for commerce secretary said renegotiating a trade deal with Mexico and Canada would likely be the incoming administration's first priority.
Mexico's peso strengthened against the dollar on Tuesday after President-elect Donald Trump said the greenback's strength against the Chinese yuan "is killing us."
"Right now we are in a situation where the currency has gone up so strong, the dollar, that we do run the risk of potentially another Mexican style crisis," David Rubenstein said.
Mexico's finance minister made these comments after the peso hit a series of record lows over fears that Trump's policies could hurt foreign investment south of the border.