"This is an important step toward de-escalation and creating critical space for diplomacy and confidence-building between Iran and the United States," Stephane Dujarric said in a statement, Anadolu Agency reported.
The statement came after US President Donald Trump said that Washington would extend its ceasefire with Iran following a request by Pakistani officials.
Dujarric said the UN encourages all parties to refrain from actions that could undermine the ceasefire and engage constructively in negotiations to reach "a sustainable and lasting" resolution.
Noting that Guterres fully supports Pakistan’s efforts to facilitate continued dialogue, Dujarric expressed hope that these diplomatic efforts would help establish the conditions necessary for a “comprehensive and durable resolution” to the conflict.
Trump's announcement came as a US delegation led by Vice President JD Vance was expected Tuesday to travel to Islamabad for a second round of face-to-face talks with Iran, though the trip was delayed.
The negotiations would have followed an initial round of high-level engagement in Pakistan earlier this month which ended without a breakthrough.
The ceasefire, initially announced earlier this month, had been set to expire Wednesday.