The central bank's monetary policy committee decided the interest rate hike unanimously, the institution said in a statement.

Market observers had been expecting the increase, the first since July last year.

Inflation last year quickened to 5.91 percent, well above the government's target of 4.5 percent.

While new President Dilma Rousseff, who only took over from predecessor Luiz Inacio Lula da Silva on January 1, had promised to bring the rate down, she has been caught by rising consumer prices.

Although hiking the interest rate will make credit purchases more expensive in Brazil, it will also further enhance the country's allure to foreign investors who are guaranteed rate-linked returns higher than for any other big economy in the world.

That will inevitably push the real up further against the dollar.

It has already soared more than 100 percent against the greenback over the past eight years and looked likely to climb further despite government efforts to tax foreign capital for fixed-income investments and heightened deposit requirements for domestic banks making foreign exchange bets against the real.

The move also makes Brazilian commodities, such as iron ore, soya beans, orange juice and coffee, more expensive on the world market, undercutting exporters' performance.

Rousseff's government has warned it will implement more measures to stop the real's rise, but many observers say they will only provide a short-term solution.

In the long run, they say, the government will have to cut back on government spending, which has ballooned in recent years.