By Rick Rothacker and Karen Freifeld Thu Dec 13, 2012 8:31pm EST (Reuters) - Bank of America Corp (BAC.N) raised the stakes in its ongoing legal battle with bond insurer MBIA Inc (MBI.N) on Thursday, saying MBIA was in default on some of its debt and filing a lawsuit related to changes in that debt. "MBIA believes that Bank of America's purported notice of default is meritless and as a result has no force and effect under the terms of the indenture," an MBIA spokesman said in an emailed statement. He termed the move "a transparent attempt to gain leverage to force MBIA Corp. to accept a discounted settlement of the over $4.5 billion that BofA owes MBIA Corp. for fraudulent and misrepresented mortgage loans." A source familiar with the matter, speaking on condition of anonymity, said Bank of America also filed suit against MBIA in a New York state court, alleging MBIA interfered in Bank of America's offer to buy the bonds. As of Thursday evening the suit was not yet publicly available. The two sides are currently in court in pretrial hearings in MBIA's 2008 breach of contract lawsuit against Bank of America subsidiary Countrywide for misrepresenting the quality of loans it insured. Reporting by Karen Freifeld in New York and Rick Rothacker in Charlotte; Writing by Ben Berkowitz; editing by Andrew Hay and M.D. Golan