Two threats lie behind the high-level talks between the West and Russia over security guarantees — Russia’s threat to invade Ukraine and the U.S. threat to impose “high-impact” financial and economic sanctions if it does.

Since last year, Russia has amassed some 100,000 troops at the Ukrainian border to increase pressure on the West and demand guarantees that NATO won’t extend membership to Ukraine or otherwise expand eastward. In December, Secretary of State Antony Blinken suggested that the United States would use sanctions “we’ve refrained from using in the past” if Russia invades.

After the three rounds of talks, Deputy Secretary of State Wendy Sherman suggested it was not clear whether Russia was prepared to de-escalate and seek a diplomatic solution. Russian Deputy Foreign Minister Sergei Ryabkov said Thursday that the talks reached “a dead end or a difference in approaches.”

As the threat of war gets more imminent, what measures might the U.S. include in its sanctions package? And are they enough to deter Russia so that it backs down? Here’s what you need to know.

The Biden administration has signaled what it is prepared to do

Before the high-stakes talks, Washington signaled to Moscow what to expect if Russia decides to invade Ukraine. The first option would be to target Russia’s largest financial institutions, placing them on the list of “specially designated nationals and blocked persons” — the U.S. SDN list. This would effectively block these banks from engaging in transactions with other international banks.

In 2014, the United States and the European Union imposed less sweeping financial sanctions on Russia. Washington didn’t put any major Russian banks on the SDN list because Russia was so closely integrated into the global financial system. The threat of a new escalation puts this option back on the table.

If such a measure weren’t implemented carefully, it might cause collateral damage. Targeting Russia’s biggest banks might have unanticipated consequences and hurt the general public, although going after less internationally connected institutions might be less risky, while remaining somewhat effective.

The second option involves imposing what the United States calls “extraordinary” export controls. This would bar exporters from selling U.S.-made or U.S.-designed technology to Russia’s defense and consumer industries, potentially hurting Russia’s ability to buy not just aircraft and automobile components, but everyday items like smartphones, too.

However, export bans usually take a toll over the long run, which means they are less effective at deterring actions in the short term. It’s unlikely that Russian decision-makers will change military policy because they fear that Russian consumers won‘t be able to upgrade to a new smartphone at some point in the future. Indeed, an embargo on consumer electronics would hurt Russian civilians rather than Russian leaders, the exact opposite of what targeted “smart” sanctions are supposed to accomplish.

Targeting Russia’s aerospace and arms industry might align better with the U.S. objective to deprive the Russian government of additional revenue. Even so, the long-term effects of the embargo won’t have the immediate impact that might help change the current situation.

And the sanctions package would provide security assistance to Ukraine and arm Ukrainian insurgents to conduct a guerrilla war against Russian military aggression. This would bolster Kyiv’s defense capabilities, but it is not a sanction per se.

These measures do not add up to the “massive consequences” that the United States talked about, and they are less likely to deter Russia.

Congress is taking a harder line

On Wednesday, Senate Democrats unveiled a package of proposed sanctions that would go much further in imposing severe costs on the Russian economy and financial system. The legislation includes sweeping restrictions on Russia’s largest state-owned and private banks, on the country’s sovereign debt and on extractive industries that are key to the Russian economy, such as oil, gas, coal and minerals. In addition, the bill would also restrict Russian access to specialized financial messaging services such as SWIFT (which is a key chokepoint in the global financial infrastructure) and the Nord Stream 2 pipeline that carries gas from Russia to Europe.

If this legislation passes, high-impact sanctions would be back on the table. However, the decision over whether to use them would still rest with the Biden administration, depending on Russia’s actions after the high-level talks. The legislation would allow President Biden to determine whether Russia is engaged or is supporting a significant escalation in Ukraine compared to the military situation in early December, giving the administration some wiggle room and flexibility.

It’s not clear that sweeping sanctions are credible

The proposal for tougher sanctions raises an important question. Do the United States and its allies have sufficient appetite for stringent measures that could create economic and political fallout, and provoke Russia to retaliate?

Some officials in the Biden administration believe that the Obama administration was “too tentative and mild” in its reaction to Russia’s 2014 invasion of Crimea. However, they are finding it hard to come up with measures that could meet the necessary conditions of finding common ground with European allies (who depend on Russian gas supplies) and avoid economic self-harm and collateral damage, while shielding the United States and its allies from potential Russian retaliation. Germany, for instance, is heavily invested in Nord Stream 2 — and has warned against connecting threats against the pipeline to the conflict over Ukraine.

If Russia decides to take advantage of what it sees as Western indecision and a lack of coordination, Washington and the E.U may have to move from deterrent threats intended to prevent Russia from doing things in the future to coercive measures intended to stop Russia from doing what it is already doing. Experience suggests that coercion is usually more difficult than deterrence.

Dr. Maria Shagina (@maria_shagina) is a visiting fellow at the Finnish Institute of International Affairs and the author of “Toward a Trans-Atlantic Strategy on Russia Sanctions.”