China vowed on Saturday to continue playing a constructive role to support and implement Iran’s nuclear deal after US President Donald Trump set out a deadline for fixing “appalling flaws” in the deal, or else he announced a US withdrawal.

Chinese Foreign Minister Wang Yi told his Iranian counterpart Mohammad Javad Zarif over the phone that the implementation of the deal had not “stalled,” but might face “some new complex factors,” the official Xinhua news agency reported.

During the telephone conversation, which was held during his visit to Rwanda, Wang was quoted as saying that the continued implementation of the nuclear agreement is the responsibility of all concerned and is the common desire of the entire international community.

The agreement would support the international regime to prevent the spread of nuclear weapons, international peace and stability and resolve many “hot issues” around the world, he added.

The Chinese foreign minister called on Iran to remain calm and abide by its commitments under the agreement.

Trump agreed on Friday to extend the suspension of sanctions on Iran for the last time until there are conditions for reform of what he called “horrific defects” in the nuclear deal.

The deadline puts pressure on Europeans, key supporters of the 2015 nuclear deal, to satisfy Trump, who wants to tighten the deal by a 120-day extension agreement.

Zarif responded to his Twitter account saying the deal was “non-renegotiable” and that Trump’s position “amounts to a desperate attempt to undermine a strong multilateral agreement.”

Although Trump agreed to extend the suspension of sanctions against Iran, the Treasury Department announced new sanctions on 14 entities and individuals, including the head of the judiciary, Ayatollah Sadiq Larijani, close ally of Supreme Leader Ayatollah Ali Khamenei.

Iran said on Saturday it would respond to the new sanctions without specifying how to respond.