Bank of America Corp. says it will expand efforts to help Countrywide Financial Corp. borrowers avoid foreclosure on trouble mortgages.

The announcement came Monday as members of the Federal Reserve Board began two days of public hearings on Bank of America’s proposed $4.1 billion stock deal for Calabasas, Calif.-based Countrywide.

Liam McGee, president of Bank of America’s global consumer and small business banking operation, said the bank will modify at least $40 billion in problem loans from at least 150,000 borrowers over the next two years.

The acquisition, which is expected to close in the third quarter, would make Charlotte, N.C.-based Bank of America the nation’s largest mortgage lender in addition to the nation’s largest consumer bank.