A US State Department spokesperson said the United States had received Iran's response to the EU bid to revive the 2015 nuclear deal and would formulate its own response, CNN reported.
"We are studying it and will respond through the EU, but unfortunately it is not constructive," the State Department spokesperson said.
Iran sent its reply to the EU on Thursday after careful examination, Iranian Foreign Ministry Spokesperson Nasser Kan’ani said in a statement on Telegram.
"The sent text has a constructive approach with the aim of finalizing the negotiations," he said.
Early in August, EU officials sent the US and Iran what it called the "final text" of a revived deal to limit Tehran's nuclear program in exchange for sanctions relief.
Iran and the US have since exchanged responses on sticking points to fully implement the nuclear pact, also known as the Joint Comprehensive Plan of Action (JCPOA).
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