Iran’s nuclear chief said on Tuesday he was warning the European Union’s top diplomat that Iranian patience was running out on the bloc’s pledges to keep up oil trade despite U.S. sanctions, Reuters reported.

“If we cannot sell our oil and we don’t enjoy financial transactions, then I don’t think keeping the deal will benefit us anymore,” head of the Atomic Energy Organisation of Iran, Ali Akbar Salehi told Reuters ahead of a meeting with EU foreign policy chief Federica Mogherini in Brussels.

“I will pass certainly a word of caution to her (Mogherini): I think the period of patience for our people is getting more limited and limited. We are running out of the assumed timeline, which was in terms of months.”

Following the meeting, Mogherini said she and Salehi remained committed to safeguarding the nuclear accord.

“They equally expressed their determination to preserve the nuclear agreement as a matter of respecting international agreements and a key pillar for European and regional security,” Mogherini’s office said in a statement.

It said Mogherini also repeated the EU stance “on issues of concern such as Iran’s role in the region” - alluding to Iranian involvement in Middle East conflicts from Yemen to Syria.