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WASHINGTON, June 17 (Reuters) - Iran's plan to exceed internationally agreed curbs on its stock of low-enriched uranium amount to "nuclear blackmail" and must be met with increased international pressure, a White House National Security Council spokesman said on Monday.
"Iran's enrichment plans are only possible because the horrible nuclear deal left their capabilities intact," NSC spokesman Garrett Marquis said. "President Trump has made it clear that he will never allow Iran to develop nuclear weapons. The regime's nuclear blackmail must be met with increased international pressure."
The security council's comments followed Tehran's announcement on Monday that it would breach the curbs set in the 2015 Iran nuclear deal in 10 days.
Tensions between Iran and the United States are rising more than a year after President Donald Trump announced Washington was pulling out of the so-called Joint Comprehensive Plan of Action and would begin reimposing sanctions on Tehran.
The nuclear deal, reached during the presidency of Trump predecessor Barack Obama, requires Iran to curb its uranium enrichment capacity, capping Iran's stock of low-enriched uranium at 300 kg of uranium hexafluoride enriched to 3.67 percent or its equivalent for 15 years.
A series of more intrusive U.N. inspections under the deal have verified that Iran has been meeting its commitments.
But U.S.-Iran tensions are growing following accusations by Trump's administration that Tehran last Thursday attacked two oil tankers in the Gulf of Oman, a vital oil shipping route. Iran denies having any role. (Reporting by Steve Holland; Writing by David Alexander; Editing by Doina Chiacu and Bill Trott)
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