WASHINGTON — Some of the nation's largest banks will be scrambling to demonstrate that they can raise capital after results of government stress tests leaked out, showing many need more funds. The Treasury Department will officially release results today.

The tests were designed to gauge whether any of the nation's 19 largest banks would need more capital to survive a deeper recession. It turns out many of the banks do: Wells Fargo & Co., Citigroup Inc. and Bank of America Corp. all need billions more, regulators have told them.

The public nature of the assessments and today's planned announcement raised questions among some critics about whether the findings will reflect the banks' actual conditions.

The tests put banks through two scenarios: one that reflected expectations about the current recession and another that envisioned a recession deeper than what analysts predict.

Citigroup will need to raise about $5 billion, according to a government official briefed on the results who spoke on the condition of anonymity because he was not authorized to discuss the matter. Earlier news reports had put that dollar figure closer to $10 billion.

Regions Financial Corp. will also need to raise more money, according to people briefed on the results, as will Bank of America and Wells Fargo.

Bank of America stock rose Wednesday after reports that the Charlotte, N.C.-based company would need to collect $34 billion in additional capital. The New York Times and Wall Street Journal reported the figure. The Journal cited unidentified people familiar with the situation, while the Times quoted a bank executive.

Wells Fargo needs between $13 billion and $15 billion, according to Times and Journal reports today. GMAC, the lending arm of beleaguered automaker General Motors Corp., is said to need $11.5 billion, while State Street Corp. needs an undisclosed amount of new capital, according to the Journal.

Morgan Stanley is looking at between a $1 billion and $2 billion shortfall, according to the Times.

In all, the Journal said at least seven of the banks will need a combined $65 billion. The entire group that is deemed to need more capital will require less than $100 billion combined, according to the Times.

Stress tests have long been a part of the bank regulation system. They help regulators decide how to supervise banks and aid banks in deciding how to limit their risk. But those conversations between banks and regulators normally take place behind closed doors.

In recent weeks, the government's unprecedented decision to publicly release bank-test results has fanned speculation, with analysts predicting the findings and investors staking out trading positions.