Iran says it will break uranium stockpile limit in 10 days

Iran will break the uranium stockpile limit set by Tehran's nuclear deal with world powers in the next 10 days, the spokesman for the country's atomic agency said on Monday.

Speaking during a press conference at Iran's Arak heavy water facility, Behrouz Kamalvandi also warned that Iran has the need for uranium enriched up to 20%, just a step away from weapons-grade levels.

The announcement indicated Iran's determination to break from the landmark 2015 accord, which has steadily unraveled since the Trump administration pulled America out of the deal last year. Washington has also re-imposed tough economic sanctions on Iran, sending its economy into freefall.

Kamalvandi acknowledged that the country already quadrupled its production of low-enriched uranium and said Tehran would increase uranium enrichment levels "based on the country's needs."

That increase could be to any level, from 3.67% which is the current limit set by the nuclear deal.

Iran's needs 5% enrichment for its nuclear power plant in southern Iranian port of Bushehr and it also needs 20% enrichment for a Tehran research reactor, the spokesman said.

When uranium is mined, it typically has about 140 atoms of this unwanted isotope for every atom of U-235. Refining it to a purity of 3.67%, the level now allowed by the nuclear deal, means removing 114 unwanted atoms of U-238 for every atom of U-235.

Boosting its purity to 20% means removing 22 more unwanted isotopes per atom of U-235, while going from there to 90% purity means removing just four more per atom of U-235, he noted. Ninety percent is considered weapons-grade material.

That means going from 20% to 90% is a relatively quicker process, something that worries nuclear nonproliferation experts.

The development comes in the wake of suspected attacks on oil tankers last week in the region, which Washington has blamed on Iran.