(In paragraph 6, please read that intraday "the peso reached 19.29" not "19.52")
By Bruno Federowski
SAO PAULO, Sept 14 (Reuters) - Mexico's currency fell on Wednesday to its lowest closing level ever, with investors on edge due to uncertainty over the timing of the next U.S. interest rate increase and sinking crude oil prices.
Market expectations about U.S. monetary policy have been through a roller coaster over the last few weeks as traders sought to decipher contradictory comments by Federal Reserve policymakers and the implications of weak economic data.
Traders hope the Fed will offer more clarity following its policy meeting next week, when it is expected to leave rates unchanged.
Investors were also worried that other major central banks, such as the European Central Bank and the Bank of Japan, could be close to reducing their monetary support.
A spike in crude prices following a surprise draw in U.S. oil stocks briefly boosted demand for currencies from commodity exporters. But the move lost steam, with the Mexican peso closing at 19.21, its lowest close ever.
In intraday trading the peso reached 19.29, its lowest level in nearly three months. Mexico's benchmark IPC stock index was down 0.84 percent to 45,767.57 points, its weakest closing level since July 8.
In Brazil, recent volatility led the central bank to reduce the amount of reverse currency swaps it sells on a daily basis to 5,000 from 10,000.
Reverse currency swaps function like future dollar purchases from investors and are typically used to weaken the Brazilian real.
The real retreated 0.79 percent to close at 3.34 per dollar as traders worried that newly inducted President Michel Temer could struggle to find support among both voters and lawmakers for painful austerity measures. (Reporting by Bruno Federowski; Editing by Meredith Mazzilli and David Gregorio)