WASHINGTON — White House senior economic adviser Lawrence Summers challenged U.S. financial institutions to think about what they can do for their country by stepping up and accepting the regulations imposed upon them in the wake of the largest financial crisis since the Great Depression.

"Financial institutions that have benefited from government support can, should and must use this moment to think about what they can do for their country — by accepting the necessary regulation to protect the American people," Summers said Friday at a conference sponsored by The Economist magazine in New York. "There is no financial institution that exists today that is not the direct or indirect beneficiary of trillions of dollars of taxpayer support for the financial system."

Summers, the director of the National Economic Council, defended efforts on Capitol Hill to reform regulation in the sector. Legislators in the House and Senate are working on a broad set of reforms for financial firms, including new regulations on derivatives, credit rating agencies and banks.

"The time has come for fundamental change in the financial sector of our economy — both in how financial institutions conduct their business and how they are regulated," Summers said.

The U.S. Chamber of Commerce is lobbying against numerous aspects of the legislation, including a measure to create a Consumer Financial Protection Agency that the chamber has characterized as a new bureaucracy that will limit choices for consumers. Financial firms are concerned about new fees that lawmakers might impose on institutions to fund a mechanism to resolve an insolvent megabank so that its collapse doesn't cause collateral damage.

The House Financial Services Committee took a major step in the reform effort Thursday by approving a broad set of regulatory reforms for the derivatives industry, including a provision requiring that standardized derivatives traded by large financial institutions go through transparent clearinghouses and exchanges. The House Agriculture Committee is set to push forward work on derivatives legislation, which is expected to be coordinated with the bill approved in the committee.

"The House Financial Services Committee took an historic step in this direction Thursday when it voted to bring previously unregulated derivatives under the regulatory umbrella," Summers said.

The committee in July approved the first component of regulatory reform by approving legislation to give shareholders a broader say in bank and other corporate elections. After approving derivatives legislation, the panel plans to continue work this week on the controversial consumer-protection agency that they are expecting to write rules for mortgages and credit cards.

The committee is expected subsequently to write legislation for hedge funds, credit-rating agencies and systemically significant financial institutions — that is, those whose collapse could cause collateral damage to the markets. The Senate is expected to begin work on its own reform legislation later this year.

Responding to a question about whether more capital should have been injected into banks during the height of the crisis, Summers said there is no evidence now that the U.S. should have poured larger amounts of capital into banks. He argued that the government's massive capital injection into American International Group Inc., a $190 billion injection in exchange for an 80 percent government stake, was not a model for troubled banks.

"Whatever you thought about actions of last spring, now you have to be more comfortable that the right thing was done," Summers said. "I am not struck by anything we have observed (since the spring) that a systematic government effort to do for more financial institutions like what was done for AIG — and to do that as a matter of choice rather than as a matter of necessity — would have been an availing strategy for solving problems."