The U.S. Treasury has told Bank of America (NYSE:BAC) it needs to increase its holdings of common equity by about $35 billion within six months, bank officials said.

The bank will not be asked to raise new capital, but will be given the option of converting other forms of capital into common equity, The Washington Post reported Wednesday.

One option for the struggling bank -- one of the nation's largest -- will be for Bank of America (NYSE:BAC) to convert the $45 billion it has already received from the government from preferred shares to common stock, The New York Times reported.

The mandate for the larger capital cushion came as a result of the so-called stress tests the Treasury conducted on the country's 19 largest banks.

The stress tests, overall, are expected to show mixed results. Tests results for Bank of New York Mellon, Goldman Sachs and JPMorgan Chase are expected to show healthy reserves.

Citigroup (NYSE:C). is expected to need to new capital in addition to converting its government loans into common stock, which will give the government 36 percent of the company, the Post said.

Bank of America (NYSE:BAC) 's Chief Administrative Officer J. Steele Alphin said there are "several ways," to raise capital, adding, "the company is very healthy."