The fighting has broken an interim truce established under a Memorandum of Understanding signed by the two countries in June.
The deal sought to end hostilities that erupted in late February following US-Israeli strikes on Iran and counter attacks by Tehran across the Gulf region.
De-escalation, dialogue and diplomacy
Mr. Guterres urged all parties “to take immediate steps for de-escalation and return to the path of dialogue and diplomacy”, UN Spokesperson Stéphane Dujarric told journalists in New York.
“The Secretary-General reiterates that a return to full-scale hostilities would exact an intolerable toll on civilians and have catastrophic consequences for international peace and security and the global economy,” he said.
The UN chief also reiterated his call for the full restoration of international navigational rights and freedoms in and around the Strait of Hormuz, a crucial maritime corridor for oil and natural gas exports.
He stressed that the exercise of navigational rights and freedoms must be respected by all sides, in line with international law.
