Michael S. Barr, the Federal Reserve’s vice chair for supervision, on Monday introduced that he can be pushing for vital modifications to how America’s largest banks are overseen in a bid to make them extra resilient in instances of bother — partly by ratcheting up how a lot capital they must get them by a tough patch.

The overhaul would require the most important banks to extend their holdings of capital — money and different available belongings that can be utilized to soak up losses in instances of bother. Mr. Barr predicted that his tweaks can be “equivalent to requiring the largest banks hold an additional two percentage points of capital,” if they’re carried out.

“The beauty of capital is that it doesn’t care about the source of the loss,” Mr. Barr stated in his speech previewing the proposed modifications. “Whatever the vulnerability or the shock, capital is able to help absorb the resulting loss.”

Mr. Barr’s proposals aren’t a completed deal: They would want to make it by a notice-and-comment interval — giving banks, lawmakers and different events an opportunity to voice their views. If the Fed Board votes to institute them, their implementations will contain transition time. But the sweeping set of modifications that he set out meaningfully tweak each how banks police their very own dangers and are overseen by authorities regulators.

“It’s definitely meaty,” stated Ian Katz, an analyst at Capital Alpha who covers banking regulation.

The Fed’s vice chair for supervision, who was nominated by President Biden, has spent months reviewing capital guidelines for America’s largest banks, and his outcomes have been hotly anticipated: Bank lobbyists have for months been warning concerning the modifications he may suggest. Midsize banks particularly have been outspoken, saying that any enhance in regulatory necessities can be pricey for them, reining of their capability to lend.

Monday’s speech made clear why banks have been apprehensive. Mr. Barr needs to replace capital necessities based mostly on financial institution danger “to better reflect credit, trading and operational risk,” he stated in his remarks, delivered on the Bipartisan Policy Center in Washington.

For occasion, banks would now not be capable of depend on inside fashions to estimate some kinds of credit score danger — the prospect of losses on loans — or for notably tough-to-predict market dangers. Beyond that, banks can be required to mannequin dangers for particular person buying and selling desks for explicit asset lessons, as a substitute of on the agency degree.

“These changes would raise market risk capital requirements by correcting for gaps in the current rules,” Mr. Barr stated.

Perhaps anticipating extra financial institution pushback, Mr. Barr additionally listed present guidelines that he didn’t plan to tighten, amongst them particular capital necessities that apply solely to the very largest banks.

The new proposal would additionally attempt to deal with vulnerabilities laid naked early this 12 months, when a collection of main banks collapsed.

One issue that led to the demise of Silicon Valley Bank — and despatched a shock wave throughout the midsize banking sector — was that the financial institution was sitting on a pile of unrealized losses on securities labeled as “available for sale.”

The lender had not been required to rely these paper losses when it was calculating how a lot capital it wanted to climate a troublesome interval. And when it needed to promote the securities to lift money, the losses got here again to chunk.

Mr. Barr’s proposed changes would require banks with belongings of $100 billion or extra to account for unrealized losses and beneficial properties on such securities when calculating their regulatory capital, he stated.

The modifications would additionally toughen oversight for a wider group of huge banks. Mr. Barr stated that his extra stringent guidelines would apply to companies with $100 billion or extra in belongings — decreasing the edge for tight oversight, which now apply probably the most enhanced guidelines to banks which are internationally energetic or have $700 billion or extra in belongings. Of the estimated 4,100 banks within the nation, roughly 30 maintain $100 billion or extra in belongings.

Mr. Katz stated that the growth of robust guidelines to a wider set of banks was probably the most notable a part of the proposal: Such a tweak was anticipated based mostly on remarks from different Fed officers lately, he stated, however “it’s quite a change.”

The financial institution blowups earlier this 12 months illustrated that even a lot smaller banks have the potential to unleash chaos in the event that they collapse.

Still, “we’re not going to know how significant these changes are until the lengthy rule-making process plays out over the next couple of years,” stated Dennis Kelleher, the chief government of the nonprofit Better Markets.

Mr. Kelleher stated that normally Mr. Barr’s concepts appeared good, however added that he was troubled by what he noticed as an absence of urgency amongst regulators.

“When it comes to bailing out the banks, they act with urgency and decisiveness, but when it comes to regulating the banks enough to prevent crashes, they’re slow and they take years.”

Bank lobbyists criticized Mr. Barr’s announcement.

“Fed Vice Chair for Supervision Barr appears to believe that the largest U.S. banks need even more capital, without providing any evidence as to why,” Kevin Fromer, the chief government of the foyer group the Financial Services Forum, stated in an announcement to the news media on Monday.

“Further capital requirements on the largest U.S. banks will lead to higher borrowing costs and fewer loans for consumers and businesses — slowing our economy and impacting those on the margin hardest,” Mr. Fromer stated.

Susan Wachter, a finance professor on the University of Pennsylvania’s Wharton School, stated the proposed modifications have been “long overdue.” She stated it was a reduction to know {that a} plan to make them was underway.

The Fed vice chair hinted that extra financial institution oversight tweaks impressed by the March 2023 turmoil are nonetheless coming.

“I will be pursuing further changes to regulation and supervision in response to the recent banking stress,” Mr. Barr stated in his speech. “I expect to have more to say on these topics in the coming months.”