Brazil’s central bank announced it would sell as much as $3 billion in a spot auction on Thursday, its fourth such intervention this week amid a massive currency selloff.

Brazil's currency faced a choppy market on Monday, opening sharply lower against the U.S. dollar after renewed criticism of interest rate levels by President Luiz Inacio Lula da Silva but paring losses after a central bank intervention.

Brazil’s real has fallen to its weakest level against the dollar since the currency was introduced in 1994, undercut by investors’ frustration with President Luiz Inácio Lula da Silva's efforts to rein in government spending.

Lula da Silva has upped his criticism of the country's worrying interest rates, expressing his serious concern for Brazil's economy.

The steepening sequence of interest-rate increases contrasts with most other central banks, including the U.S. Federal Reserve, which are cutting rates.

Speaking in an interview with TV Globo aired late on Sunday, the leftist leader called the interest rate hikes "irresponsible" and said his government would "take care of that"

Brazilian President Luiz Inacio Lula da Silva slammed what he sees as the country's excessively high interest rates, saying that borrowing costs were "the only thing wrong" with Brazil at the moment.