The Brazilian real was little changed, but was expected to remain volatile as traders sought to influence the month-end Ptax rate that is used as a benchmark for futures contracts.
Investors, concerned about a protracted US-China trade war that has roiled financial assets for much of the year, played down expectations that the meeting between Trump and Chinese President Xi Jinping at the G20 Summit on Saturday will resolve trade tensions between the two countries.
"We don't think there will be anything concrete on the trade talks with Trump and Xi. The best-case scenario would be some sort of ceasefire," said Morten Lund, an analyst with Nordea Markets in Denmark.
Market sentiment this month has been largely driven by the meeting on Saturday on concerns that a lack of resolution in trade tensions will hurt world economic sentiment.
Mexican President-elect Andres Manuel Lopez Obrador's decision to cancel a partially-built airport for Mexico City in late October has left investors wondering how he will manage the economy. He will give an inauguration speech on Saturday.
"AMLO (Lopez Obrador) is taking office and it is with a lot of nervousness that the markets are looking at it," Lund said.
The latest minutes from Mexico's central bank meeting showed policymakers thinking it was "indispensable" to hike interest rates to counter confusion over future policies.
Despite the peso's intraday losses, the currency was on track to post its first gain in nine weeks as the US dollar has come under pressure after dovish comments from the Federal Reserve chief Jerome Powell.
The signing early on Friday of a revised US-Mexico-Canada trade pact had little impact on the currency's trajectory.
The real was down nearly 3 percent for the month as skepticism built over President-elect Jair Bolsonaro's efforts to reduce Brazil's high fiscal deficit, including plans for an overhaul of the pension system.
The country's main Bovespa index edged higher, hitting a new record high. Shares of Cosan SA Industria e Comércio rose more than 2.5 percent after the energy company announced a tender offer to repurchase $100 million of its US shares.