WASHINGTON, Oct. 25 (Reuters) – The top US envoy to Iran said on Monday that efforts to revive the 2015 Iran nuclear deal were now in a “critical phase,” saying Tehran’s reasons for failing to not resume talks were exhausted.

Speaking to reporters, US Special Envoy for Iran Robert Malley said Washington was increasingly concerned that Tehran would continue to delay resumption of talks, but said it had other tools to prevent Iran from developing a nuclear weapon and would use them if necessary.

“We are in a critical phase of efforts to see if we can revive the JCPOA,” said Malley, referring to the agreement formally known as the Joint Comprehensive Plan of Action. “We have had a hiatus of several months and the official reasons given by Iran as to why we are in this hiatus are very slim.”

While asserting that the window for the United States and Iran to resume compliance with the agreement would eventually close, Malley stressed that the United States would still be willing to engage in diplomacy with the Iran although they were considering other options to prevent Tehran from obtaining the bomb.

Then-US President Donald Trump abandoned the pact in 2018 and reimposed tough US sanctions. About a year later, Iran began to violate some of the terms of the agreement, notably on uranium enrichment. Uranium enrichment may provide a route to obtain fissile material for an atomic bomb, an ambition Iran denies.

Reporting by Humeyra Pamuk and Arshad Mohammed Editing by Paul Simao

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