SAO PAULO, Dec 11 (Reuters) - Brazilian markets seesawed ahead of a crucial week for the government's plans to streamline the social security system and curb public debt. Investors widely see the unpopular bill as crucial to regaining an investment grade rating, meeting budget laws and avoiding a fiscal crisis. But lawmakers have shown strong resistance to the constitutional amendment, raising the threat that a lower house vote is delayed to early 2018. The government agreed with lawmakers to schedule a Dec. 18 vote on the bill, the week before Christmas recess. But President Michel Temer acknowledged the vote could happen only next year, dialing back on last week's strict rhetoric.
An early 2018 vote would edge dangerously close to presidential and parliamentary elections, making approval more unlikely. The Brazilian real firmed 0.1 percent, while the benchmark Bovespa stock index rose 0.8 percent. Trading in most Latin American markets was muted as investors avoided making big bets ahead of central bank meetings across the region. Central banks in Mexico, Colombia, Chile and Peru will meet throughout the week to set benchmark interest rates. Also helping to foster caution, the Federal Reserve is scheduled to release its monetary policy statement on Wednesday. The Fed is widely expected to raise interest rates, and is seen possibly tightening two or three times in 2018. But still-sluggish inflation and wage growth has clouded next year's policy outlook.
Key Latin American stock indexes and currencies at 1500 GMT:
Stock indexes daily % YTD % change change
MSCI Emerging Markets 1119.92 0.82 28.82 MSCI LatAm 2728.36 0.97 15.44 Brazil Bovespa 73286.02 0.76 21.68 Mexico S&P/BVM IPC 47717.50 0.3 4.55 Chile IPSA 4956.77 1.42 19.40 Chile IGPA 24930.92 1.28 20.24 Argentina MerVal 27163.48 1.2 60.56 Colombia IGBC 10967.34 0.88 8.29 Venezuela IBC 1292.52 -3.19 -95.92 Currencies daily % YTD % change change
Brazil real 3.2898 0.13 -1.23 Mexico peso 18.9920 -0.41 9.22 Chile peso 656.7 -0.17 2.13 Colombia peso 3017.74 -0.29 -0.54 Peru sol 3.235 0.00 5.53 Argentina peso (interbank) 17.2800 0.00 -8.13 Argentina peso (parallel) 17.88 0.00 -5.93
(Reporting by Bruno Federowski; Editing by Andrew Hay)