Guterres' appeal to Washington comes amid talks to revive the Joint Comprehensive Plan of Action, under which Iran accepted curbs on its nuclear programme in return for a lifting of many foreign sanctions against it.
The talks are aimed at determining which sanctions the United States should lift and the measures Iran has to take in order to rein in Tehran's nuclear programme.
Iranian President Hassan Rouhani has criticised Europe's "inactivity on JCPOA commitments" and added that Iran is committed to "preserving the JCPOA and is the only party that has paid a price for it."
Iran's stockpile of enriched uranium is now more than 14 times over the limit set down in its 2015 deal with world powers, the UN's nuclear agency reports.
Secretary of State Antony Blinken told European allies that the US is prepared to talk to Iran about both countries returning to compliance with a 2015 deal that aims to stop Tehran from developing a nuclear weapon.
Recent statements from within Iran point towards a showdown with the US, but one that hopes to sway domestic politics too.
As President-elect Joe Biden readies to take office next month, European powers are hopeful the US will return to the pact but Iran has already abandoned limits placed on its nuclear activity laid down in the initial deal.
Iran's uranium enrichment level has passed 4.5 percent, exceeding the cap set by the 2015 nuclear deal.
European leaders' plan to trade with Iran might not be enough to encourage businesses and banks to defy the US-imposed sanctions.
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