A stretch of strong US economic data, the latest a report on Wednesday showing services activity at an 11-month high, have boosted expectations that the Federal Reserve will act soon, denting demand for higher-yielding emerging market currencies.
The Brazilian real weakened 0.5 percent and the Mexican peso slipped 0.3 percent.
The mood was somewhat less bearish in stock markets, however, as a stronger US economy could translate into demand for exports from emerging markets.
MSCI's emerging benchmark hit a one-week high, following developed bourses higher and lifted by gains across Asia , Turkey and parts of central and eastern Europe.
Brazil's benchmark Bovespa stock index rose 0.1 percent, supported by rising shares of state-controlled oil company Petr?leo Brasileiro SA and planemaker Embraer SA.
Shares in meatpacker JBS SA fell 1.4 percent as investors booked profits following a sharp increase the day before, limiting gains in the index.