US Secretary of State Mike Pompeo will begin talks in coming days to persuade allies in Europe, the Middle East and Asia to press Iran to return to negotiations over its nuclear and missile programs.
The open question is whether the allies, and above all Iran, will agree to resume full-fledged talks, having just seen the United States withdraw from the 2015 Iran nuclear deal and renege on its promises under the landmark arms control accord.
The US hope is that Iran will be dragged to the table by the resumption of US sanctions - and possibly the imposition of more - which would penalise European and other companies and likely cripple Iran's oil-driven economy.
A senior State Department official said discussions with Britain, France and Germany, as well as Japan, Iraq and Israel had already taken place since US President Donald Trump on Tuesday pulled out of the nuclear pact.
"The composition of what happens when we sit down with the Iranians is several stages out," a senior State Department official said, adding talks would focus on how to raise pressure on Iran to bring it to the negotiating table.
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Trump's decision opens the door to greater US confrontation with Tehran and strains relations with America's closest allies.
Washington has given grace periods of 90 days to six months for companies and countries to wind down their trade with Iran, including reducing purchases of Iranian oil.
Even though companies can seek US Treasury licences to continue operating in Iran beyond the deadlines, the threat of US sanctions will likely force them out, experts say.
Companies will also have to assess whether they could face revived secondary sanctions, which would target sectors of the Iranian economy including energy, petrochemicals, shipping, financial and banking.
"The ultimate goal is to lay the groundwork for getting everyone back to the table and negotiating a new deal," the State Department official said.
Several US officials have acknowledged there is no "Plan B" if Washington cannot win the support of allies - and Iran - to negotiate a new, expanded agreement that would end Iran's nuclear program, restrain its ballistic missile program, and curb its support for groups in Syria, Lebanon, Yemen and Iraq.
