(Updates prices, adds detail on Mexico peso) SAO PAULO, May 21 (Reuters) - Brazil's real gained more than 1 percent on Monday after the country's central bank boosted its currency swap program, while Mexico's peso weakened past 20 per dollar to a more than one-year low. Brazil's central bank on Friday had said it would triple the currency swap contracts - equivalent to operations to sell dollars in futures markets - offered daily, after the real fell to its lowest level in more than two years. The real on Monday rose 1.35 percent, although traders said the currency might have risen more had it not been for market caution ahead of the scheduled release on Tuesday of the Brazilian central bank minutes. Mexico's peso briefly blew past 20 per dollar, touching its weakest level since March 2017, before slightly rebounding. The peso is likely to trade weaker than 20 to the dollar as talks drag out to renegotiate the North American Free Trade Agreement, analysts at Mexico's Banco Base said. U.S. Treasury Secretary Steven Mnuchin on Monday said major issues remained among the United States, Canada and Mexico to rework the treaty, and that there was no specific deadline.
In Argentina, the volatile peso strengthened 0.23 percent amid optimism over ongoing efforts by the government to obtain a financing line from the International Monetary Fund.
Stocks suffered across Latin America, led by Brazil's Bovespa index, down 1.28 percent, and Mexico's IPC index , down about 0.80 percent. In Brazil, shares of iron ore producer Vale S.A. fell more than 3 percent, in line with the drop in China's iron ore futures to their weakest level in two weeks.
Key Latin American stock indexes and currencies at 1954 GMT:
Stock indexes daily % YTD %Latest change changeMSCI Emerging Markets 1139.29 0.14 -1.79MSCI LatAm 2702.53 0.04 -4.48Brazil Bovespa 82016.72 -1.28 7.35Mexico IPC 45296.01 -0.81 -8.22Chile IPSA 5667.86 -0.38 1.86Chile IGPA 28679.66 -0.29 2.50Argentina MerVal 31768.11 -0.32 5.66Colombia IGBC 12107.50 -0.16 6.48Venezuela IBC 22795.88 -0.66 1704.70Currencies daily % YTD %change change
Latest
Brazil real 3.6891 1.35 -10.19Mexico peso 19.8550 0.43 -0.79Chile peso 636.5 0.00 -3.43Colombia peso 2875 1.52 3.72Peru sol 3.283 0.12 -1.40Argentina peso 24.3750 0.23 -23.69
(interbank)
Argentina peso 25.3 0.40 -23.99
(parallel)
(Reporting by Gram Slattery, Claudia Violante, Miguel Angel Gutierrez and Daina Beth Solomon Editing by Paul Simao and Lisa Shumaker)