Iran has warned its next step in reducing commitments under the 2015 nuclear deal will be stronger, with a senior nuclear official saying that 20% uranium enrichment is an option. 

Spokesman for Iran's Atomic Energy Organization Behrouz Kamalvandi said Monday Tehran has passed the 3.67% uranium enrichment cap set by a 2015 nuclear deal and reached about 4.5%.
"Twenty percent is not needed now, but if we want we will produce it. When we've put aside 3.67% enrichment we have no obstacle or problem with this action," Kamalvandi said.
Options for enriching at higher levels have been discussed with the Supreme National Security Council, the spokesman said. 
"There is the 20% option and there are options even higher than that but each in its own place. Today if our country's needs are one thing, we won't pursue something else just to scare the other side a little more. But they know it's an upward trend," he said. 
Kamalvandi said increasing the number of centrifuges is an option for Iran's third step in reducing its commitments to the nuclear deal, noting that restarting IR-2 and IR-2 M centrifuges is an option.
The remaining European signatories to the nuclear deal, he said, should act quickly to fulfill their promises because Iran will continue reducing its commitments to the deal until it achieves a result.