There is a rumor circulated on Wall St. that JP Morgan (NYSE: JPM) will takeover Bank of America (NYSE: BAC) within the week. The government will support the deal with a $100 billion investment in preferred shares issued by the combined entity. Alternatively, the government may guarantee the value of a large pool of Bank of America assets. The word is that Treasury Secretary Geithner has discussed the transaction with JP Morgan CEO Jamie Dimon.The "merger" would completely destroy the value of BAC's common shares.

The government feels that the deal may be necessary as Bank of America struggles unsuccessfully to close several transactions to bolster its balance sheet. The Wall Street Journal reported that the financial firm will need to raise $200 billion which would be another possible event that would wipe out common shareholders.

Bank of America's fortunes have been hurt by events in just the last few days. A New York State judge agreed to allow institutional investors to intervene in an $8.5 billion settlement between the bank and groups that lost money on mortgage-backed securities. China Construction Bank Corp said Bank of American will continue to hold 50% of its share in the foreign financial firm. Many investors hoped Bank of America would sell its entire stake to raise money. Several analysts believe that the costs of owning mortgage firm Countrywide Credit have grown unexpectedly large.

Under federal law, JP Morgan and Bank of America could not combine because together they would have too large a share of several financial markets in the US. Treasury would apparently work with other government agencies to have those rules suspended and then the new combined bank would sell assets to get back into compliance later.

The government's preference for a deal with JP Morgan rather than a federal takeover may be because it does not want to set the precedent of Washington owning one of the world's largest banks "paid for" with taxpayer money.

Note: Credit default swap insurance on the bank's unsecured debt jumped 64 basis points to 435 basis points, meaning it would cost $435,000 per year for five years to insure $10 million in bonds, according to Markit (via Reuters)