WASHINGTON — The most punishing sanctions that U.S. officials have threatened to impose on Russia could cause severe inflation, a stock market crash and other forms of financial panic that would inflict pain on its people — from billionaires to government officials to middle-class families.

U.S. officials vow to unleash searing economic measures if Russia invades Ukraine, including sanctions on its largest banks and financial institutions, in ways that would inevitably affect daily life in Russia.

But the strategy comes with political and economic risks. No nation has ever tried to enact broad sanctions against such large financial institutions and on an economy the size of Russia’s. And the “swift and severe” response that U.S. officials have promised could roil major economies, particularly those in Europe, and even threaten the stability of the global financial system, analysts say.

Some analysts also warn of a potential escalatory spiral. Russia might retaliate against an economic gut punch by cutting off natural gas shipments to Europe or by mounting cyberattacks against American and European infrastructure.

The pain caused by the sanctions could foment popular anger against Russia’s president, Vladimir V. Putin. But history shows that the country does not capitulate easily, and resilience is an important part of its national identity. U.S. officials are also sensitive to the notion that they could be viewed as punishing the Russian people — a perception that might fuel anti-Americanism and Mr. Putin’s narrative that his country is being persecuted by the West.

From Cuba to North Korea to Iran, U.S. sanctions have a mixed record at best of forcing a change in behavior. And while the Biden administration and its European allies are trying to deter Mr. Putin with tough talk, some experts question whether they would follow through on the most drastic economic measures if Russian troops breached the border and moved toward Kyiv, Ukraine’s capital.

President Biden has said he will not send American troops to defend Ukraine. Instead, U.S. officials are trying to devise a sanctions response that would land a damaging blow against Russia while limiting the economic shock waves around the world — including in the United States. Officials say that for now, the Biden administration does not plan to target Russia’s enormous oil and gas export industry; doing so could drive up gasoline prices for Americans already grappling with inflation and create a schism with European allies.

But many experts on sanctions believe that the boldest sanctions against Russia’s financial industry, if enacted, could take a meaningful toll.

“If the Biden administration follows through on its threat to sanction major Russian banks, that will reverberate across the entire Russian economy,” said Edward Fishman, who served as the top official for Russia and Europe in the State Department’s Office of Economic Sanctions Policy and Implementation during the Obama administration. “It will definitely affect everyday Russians.”

Mr. Fishman added: “How are you going to change Putin’s calculus? By creating domestic disturbances. People will be unhappy: ‘Look what you did — all of a sudden my bank account is a fraction of what it was? Thanks, Putin.’”

Sanctions imposed after Mr. Putin annexed Ukraine’s Crimean Peninsula in 2014 and gave military support to an insurgency in the country’s east created a modest drag on Russia’s economy. Those penalties and later ones took a surgical approach, heavily targeting Mr. Putin’s circle of elites as well as officials and institutions involved in aggression against Ukraine, in part to avoid making ordinary Russians suffer.

U.S. officials say the impact of sanctions now would be categorically different.

Washington is looking to take a sledgehammer to pillars of Russia’s financial system. The new sanctions that American officials are preparing would cut off foreign lending, sales of sovereign bonds, technologies for critical industries and the assets of elite citizens close to Mr. Putin.

But the real damage to Russia’s $1.5 trillion economy would come from hitting the biggest state banks as well as the government’s Russian Direct Investment Fund, which has prominent Western executives on its advisory board. The Treasury Department would draw from its experience targeting Iranian banks under President Donald J. Trump, though Iran’s banks are much smaller and less integrated into the global economy than Russian banks.

Once the department puts the Russian banks on what officials call its “game over” sanctions list, known as the S.D.N. list, foreign entities around the world would stop doing business with the banks, which would have a big effect on Russian companies.

The United States would also enact sanctions to cut lending to Russia by foreign creditors by potentially $100 billion or more, according to Anders Aslund, an economist and an author of an Atlantic Council report on U.S. sanctions on Russia. Though Russia has taken steps since 2014 to rely less on foreign debt for expenses, such a loss could still devalue the ruble, shake the stock market and freeze bond trading, Mr. Aslund added.

His report estimated that the 2014 sanctions reduced Russia’s annual economic growth by up to 3 percent, and new sanctions could bite much harder.

For an average Russian, the harshest U.S. measures could mean higher prices for food and clothing, or, more dramatically, they could cause pensions and savings accounts to be severely devalued by a crash in the ruble or Russian markets.

“It would be a disaster, a nightmare for the domestic financial market,” said SergeyAleksashenko,a former first deputy chairman of the Central Bank of Russia and former chairman of Merrill Lynch RussiaHe noted that the ruble had already fallen more than 10 percent from its October value against the dollar, amid increasing talk of Western sanctions.

In a sign of the growing seriousness, officials from the National Security Council have been talking with executives from some of Wall Street’s largest banks, including Goldman Sachs, Citigroup, JPMorgan Chase and Bank of America, about the stability of the global financial system in the wake of potential sanctions.

The European Central Bank has also warned bank lenders to Russia about risks if the United States imposes sanctions and has asked about the sizes of their loans.

For now, though, American officials are not considering any immediate sanctions on the foundation of Russia’s economy: its oil and gas exports.

​​European nations rely on natural gas from Russia, and several U.S. allies, notably Germany, prefer that Washington refrain from disrupting the Russian energy industry. Analysts say sanctions that limit Russia’s ability to export oil and gas would be by far the most powerful weapon against the Russian economy, and perhaps the most effective economic deterrent against an invasion of Ukraine, but they would also cause pain in Europe and the United States.

“At some point, the West will have to sacrifice a little bit of its well-being if the goal is to deter Putin,” said Maria Snegovaya, a visiting scholar at George Washington University and an author of the Atlantic Council report.

“U.S. inflation further constrains the administration’s actions,” she added. “Inflation is already unprecedented for the last 30 years. Any action against Russia that is dramatic will lead to changes in oil and gas prices.”

Though the United States and European nations constantly discuss Russian natural gas exports, the sale of crude oil matters far more to Mr. Putin’s economy, so sanctions on oil could have a powerful effect, said Mr. Fishman, the former State Department official.

“Oil is the lifeblood of their economy and of the Kremlin’s ability to project power,” he said, noting that the United States could use sanctions to restrict the supply of goods and services to Russia’s oil production industry, and even pressure allies to reduce their purchases of Russian oil.

In Washington, the names of a dozen Russian state-owned and private banks have circulated as potential targets of Treasury Department sanctions. They are listed in Ukraine aid bills introduced by Democratic members of Congress this month. The bills call for sanctions on at least three of the Russian banks if Mr. Putin invades Ukraine.

Russia’s two largest banks, Sberbank and VTB, are on the list. Sberbank has about a third of the assets in the country’s banking sector, and VTB has more than 15 percent, according to Ms. Snegovaya. Mr. Fishman noted that most Russians pay their mortgages to Sberbank. Though Russia’s major banks already have some level of sanctions on them, if they were put on the Treasury Department’s S.D.N. list, the damage to the economy could be profound and long-lasting.

But the Biden administration could take a more cautious approach and impose sanctions only on lesser Russian state-owned banks or limit penalties against Sberbank and VTB to their investment arms. The Treasury Department could also deploy sanctions against banks that fall short of putting them on the S.D.N. list; it could restrict banks from doing any transactions involving dollars, for instance.

And American officials are hesitant to cut off the Russian financial system from SWIFT, a critical electronic network that connects thousands of banks worldwide.

In recent years, sanctions on some Russian entities have had unintended consequences that have caused American officials to think twice. In April 2018, the Treasury Department put Oleg Deripaska, a Russian businessman close to Mr. Putin, and six other oligarchs on the S.D.N. list. Mr. Deripaska owned Rusal, the world’s second-largest aluminum producer, and the sanctions caused a surge in global aluminum prices. The Treasury Department lifted sanctions on his main companies in December 2018.

The technology sanctions against Russia would emulate the kind that the Trump administration used to hobble Huawei, the Chinese telecommunications company. The Commerce Department would invoke what it calls the foreign direct product rule, which bars American companies from providing technology to companies under sanction, demolishing the supply chain needed to produce advanced technologies. One aim would be to hamper the growth of strategic industries in Russia, including its oil and gas sector and defense industry.

“I think the administration is learning from what the U.S. has done vis-à-vis Huawei,” said Christopher Miller, co-director of the Russia and Eurasia program at Tufts University’s Fletcher School.

China’s president, Xi Jinping, may be inclined to help Mr. Putin, given their shared desire to weaken Washington’s global standing. But it is not clear that Beijing would throw Russia a robust lifeline. After the 2014 sanctions, four Chinese state-owned banks declined to do business with Russian institutions in order to avoid running afoul of Washington. And when Russia tried to sell gas to China at a high price, Chinese officials bargained them down.

Some analysts worry less about whether Russia can blunt the pain of American sanctions than whether they might cause Mr. Putin to escalate his showdown with the West.

“If the sanctions are really that momentous and Russia is fighting its biggest war since World War II on an issue of vital importance, they will likely retaliate,” said Samuel Charap, a former State Department official who is now an analyst with the RAND Corporation.

Mr. Charap added that Moscow could conduct new cyberattacks against the United States and American financial giants. The Department of Homeland Security issued a bulletin last weekend warning of Russian cyberretaliation.

“We go after their big banks,” he said, “they would likely go after ours.”