United Nations Secretary-General António Guterres has welcomed US President Donald Trump’s decision to extend the ceasefire with Iran, a spokesperson for his office said.

“This is an important step toward de-escalation and creating critical space for diplomacy and confidence-building between Iran and the United States,” spokesperson Stéphane Dujarric said, quoted by Ada Derana.

The Secretary-General’s office encouraged all parties to build on the momentum by refraining from violating the ceasefire and participating constructively in negotiations.

Guterres expressed support for Pakistan’s role in facilitating the talks and said he hoped Islamabad’s efforts would help create the conditions for a “comprehensive and durable resolution to the conflict”, Dujarric added.

Trump on Tuesday extended the ceasefire indefinitely without setting a new deadline, saying Washington would continue its blockade of Iran’s ports until Tehran submits a “unified proposal”. Vice President JD Vance’s planned visit to Islamabad was cancelled, and Iran has not confirmed whether it will send a delegation.

The UN endorsement comes as markets remain tentative, with Brent crude trading around $98.32 a barrel and Iranian military commanders threatening Gulf oil production sites in a parallel escalation.