By Pete Schroeder and Lisa Lambert

The nearly 150-page report suggested more than 100 changes, most of which would be made through regulators rather than Congress, Treasury Secretary Steven Mnuchin said in an interview. (http://bit.ly/2sVxOlt)

"We were very focused on, what we can do by executive order and through regulators," he said. "We think about 80 percent of the substance in the report can be accomplished by regulatory changes, and about 20 percent by legislation."

Republican President Donald Trump has gradually been nominating heads of financial agencies to carry out his agenda, but only Mnuchin and Securities and Exchange Commission Chairman Jay Clayton have been approved by Congress. Other agencies are operating under "acting" chiefs or have leaders appointed by Trump's Democratic predecessor, Barack Obama.

Changes proposed by the Treasury Department include easing up on restrictions big banks now face in their trading operations, lightening the annual stress tests they must undergo, and reducing the powers of the Consumer Financial Protection Bureau (CFPB), which has been aggressively pursuing bad behaviour by financial institutions.

The plan would also expand the authority of the Financial Stability Oversight Council, which is chaired by Mnuchin, and change the way global capital standards are implemented to give U.S. banks a leg up against foreign rivals. Smaller banks would get some relief as well: Lenders with $50 billion or less in assets would have to jump through fewer regulatory hoops than rivals with multitrillion-dollar balance sheets.

The industry has long sought many of the proposed changes, which would mostly benefit banks like JPMorgan Chase & Co, Bank of America Corp, Citigroup Inc, Wells Fargo & Co, Goldman Sachs Group Inc and Morgan Stanley.

Industry trade groups applauded the proposal on Monday evening, though some said they wished there were more specifics on tricky questions, such as what level regulators should set for banks' assets before subjecting them to stricter rules.

"This is the first time in a while where there's been an official undertaking where our concerns resonated with the folks in the driver's seat," said Rich Foster, senior counsel for regulatory and legal affairs at the Financial Services Roundtable, a trade group.

Representatives for the six largest U.S. banks declined to comment, did not immediately respond or said they were reviewing the document.

Reform advocates and Democratic lawmakers were quick to criticize the plan as a handout to Wall Street and a dangerous one for U.S. consumers who lost homes and jobs during the 2007-2009 financial crisis.

Democratic Senator Elizabeth Warren, a critic of Wall Street, said it would "make it easier for big banks to cheat their customers and spark another financial meltdown." Her Democratic colleague Senator Sherrod Brown noted that Treasury consulted with industry groups more than consumer groups, by a ratio of 17-to-1, while developing its report.

"The Treasury proposal advances ideas that have been pushed by industry lobbyists since Dodd-Frank was passed," said Lisa Donner, executive director of Americans for Financial Reform. "We need more effective regulation and enforcement, not rollbacks driven by Wall Street and predatory lenders."

Mnuchin said the regulatory overhaul is needed to grow the economy, give consumers more choices and ensure U.S. taxpayers would not have to bail out big banks again. While the Trump administration has said it wants to protect consumers, existing rules limit their access to loans and investment products they want.

By trying to make many of the changes through regulatory agencies, the Trump administration may avoid a lengthy and perhaps futile battle with Democratic lawmakers.

Although the White House and Congress are led by Republicans, Democrats in the Senate can block legislation and are unlikely to support any overhaul that eases rules on big banks. Some of the Treasury's proposals, like defanging the CFPB, would require new laws to be written and therefore face an uphill political battle.

The report, which focused on banks, is the first of four examinations being carried out by the Treasury Department after Trump pledged to do a "big number" on the Dodd-Frank reform law. Proposals on capital markets, clearing houses and derivatives as well as the insurance and asset management industries and financial innovation and banking technology will come later.

(Reporting by Pete Schroeder and Lisa Lambert in Washington; Writing by Lauren Tara LaCapra; Editing by Diane Craft and Lisa Shumaker)