The banking industry on Tuesday defended a controversial new fee on debit cards as some Democrats called on consumers to abandon financial institutions that impose the charge.

Rep. Brad Miller (D-N.C.) introduced a bill that would make it easier for customers to close their accounts and prohibit banks from assessing fees for the process. Meanwhile, Sen. Richard J. Durbin (D-Ill.) sent a letter to community banks and credit unions in his home state urging them to “seize this competitive opportunity” to woo consumers away from larger institutions.

“Politicians may not have the highest approval ratings, but I don’t think Wall Street banks and credit cards do either,” Durbin said.

The debate centers on a $5 monthly fee that Bank of America plans to begin charging next year to customers with the most basic checking accounts who use their debit cards to shop. Though Bank of America is the first major bank to adopt the fee, Wells Fargo and Chase are testing the charge and some regional banks have already instituted it.

Earlier this week, President Obama criticized the move as a way for banks to pad their profits at the expense of consumers. The American Bankers Association, a trade group, fired back Tuesday, accusing Washington of attempting to control private-sector prices.

“It’s disappointing and puzzling that the president would attack a private corporation for responding to government price-fixing that has fundamentally altered the economics of offering a debit card,” ABA President Frank Keating said.

Banks say the fees are the consequence of a new federal rule that took effect Saturday limiting the amount of money they can collect from merchants each time a shopper swipes a debit card. The regulation cuts the fee by roughly half, to 24 cents for an average $38 transaction, costing the banks an estimated $8 billion to $10 billion.

The new monthly charges have angered many customers, and Bank of America’s Web site has been intermittently down in recent days. A spokeswoman said the company is committed to “clear and transparent pricing,” and that the fee will help allow it to “continue providing secure and efficient methods of payment for our customers.”

The controversy has weighed on Bank of America, which is grappling with bad loans and lawsuits stemming from shoddy mortgages. On Monday, the bank’s stock fell below $6 for the first time since the financial crisis in 2009. Shares again fell Tuesday, before rallying just before the close to end up by 4.2 percent to $5.76.

Some financial institutions have tried to turn the outrage into opportunity. USAA, which caters to members of the military and their families, said it is committed to offering free checking accounts and debit cards. PNC touted its free debit card with the slogan “Achievement: paying for your groceries, not your debit card.” The Credit Union National Association, a trade group, said traffic on its Web site,, has jumped eightfold since news of Bank of America’s fee.

“Our point is, if you’re upset, you should do something about it,” CUNA chief executive Bill Cheney said.

But community banks and credit unions must walk a fine line. They oppose the new rule even though they are technically exempted from it, citing concerns that the market would eventually force them to accept lower debit-card revenue anyway.

“It’s certainly something community banks don’t ever want to have to do, but their hands may be tied,” said Camden R. Fine, chief executive of the Independent Community Bankers of America, a trade group.