NEW YORK (CNN) -- Banks have launched public relations campaigns to bring in customers and soothe nerves, with ads offering "peace of mind" and other promises.

Citigroup, along with JPMorgan Chase, Wells Fargo and Bank of America got the biggest chunks of the bailout.

But what's not public is what they are doing with the billions in federal bailout money they've received -- the money doled out through a $700 billion rescue plan so banks could start lending again.

CNN contacted the banks that were given the biggest chunks of the bailout: Citigroup, JPMorgan Chase, Wells Fargo and Bank of America.

The latter received $15 billion as part of the federal Troubled Assets Relief Program (TARP).

Where the money went is not clear.

"We are using the TARP funds to build our capital and make every good loan that we can," Bank of America said. The bank said it expects to release more information in its fourth quarter earning report.

Citigroup, JPMorgan Chase and Wells Fargo each received $25 billion -- the largest amount given to any bank.

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Wells Fargo said it can't provide any details until it releases its fourth quarter statement, though the bank said it intends to use the money to help customers avoid foreclosure.

Citigroup said it was using TARP money to help expand the flow of credit and had formed a special committee to oversee the TARP money.

JPMorgan Chase pointed out that it recently bought more than $1 billion in Illinois bonds and plans to lend $5 billion to nonprofit and health care companies.

"What the banks have said largely is that we're using the money to stimulate the economy, to get the economy moving," said Sarah Binder, a senior fellow at The Brookings Institution, a Washington think tank. "That's far, far too general to know what ... the banks are doing with the money."

The vague responses from the banks should not come as a shock, said one U.S. House Financial Services Committee member who opposed the bailout.

"One of the fundamental problems with the Wall Street bailout was the people who had caused the problem were never called in front of Congress to explain what they had done, what needed to be done," said Rep. Thaddeus McCotter, a Michigan Republican.

Congress did not put conditions on the bailout money, leaving lawmakers to press the Treasury Department for transparency after the money was handed out.

Critics say Congress needs to demand conditions before the second round of bailout money is distributed.

Earlier this month, members of a key congressional committee blasted the Treasury for its handling of the bailout, saying it lacks appropriate measures to ensure the bailout is working. At a hearing held by the Financial Services Committee, chairman Barney Frank, D-Massachusetts, accused the Treasury of failing to address its obligation to address foreclosures and enforce lending obligations on banks.

The hearing served as a follow-up to two reports on how the Treasury has conducted its bailout program, including the Congressional Oversight Panel's report on TARP, as well as a GAO report delivered to lawmakers that called for more accountability and transparency.

Congressmen on both sides of the aisle used the scathing reports as a launching pad, lambasting the Treasury for a general lack of clarity about its strategy as well as a dearth of measures that ensure banks are using the bailout funds for their intended purposes.

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