Iran's president is warning Europe that Tehran will “take the next step” in increasing its uranium enrichment this coming Sunday.

The comments Wednesday by President Hassan Rouhani further increases pressure on European partners to salvage the unraveling 2015 nuclear deal following the U.S. withdrawal from the accord last year.

Rouhani says: “If you want to express regret and issue a statement, you can do it now.” President Donald Trump pulled America from Iran's nuclear deal last year and restored crippling economic sanctions.

Iran this week breached a low-enriched uranium stockpile limitation set by the deal and said by Sunday it would increase its enrichment of uranium closer to weapons-grade levels if Europe does not offer it a new deal.