Iran’s so-called breakout time could drop to “a matter of weeks” if the country continues to violate its terms of the landmark nuclear deal, US Secretary of State Antony Blinken said on Monday.

During a House Foreign Affairs Committee hearing, Blinken said it remains to be seen whether the Iranians are “willing and prepared” to resume compliance with the 2015 nuclear deal known as the Joint Comprehensive Plan of Action (JPOCA).

The JCPOA set curbs on the purity and amount of Iran’s enriched uranium stockpile. The world powers that signed the deal estimated it would take Iran at least a year to produce enough weapons-grade enriched uranium to develop a nuclear weapon in the event that it reneged on the agreement. Since former President Donald Trump unilaterally withdrew from the JCPOA and reimposed harsh economic sanctions, Iran has steadily violated its obligations under the deal.

The original signatories to the deal have been meeting in Vienna to reach an agreement on a revived nuclear deal, but Tehran and Washington are at odds over which of them will make the first move. In the meantime, Iran’s program is "galloping forward,” Blinken said, referencing Iran’s increased uranium enrichment and recent use of advanced centrifuges.