"The JCPOA was a deal that we felt was the best possible deal that was achievable, none of us ever pretended that it was a perfect deal, but actually, it did deliver a number of important measures as I think everyone benefits from. So, we really just encourage the United States to start talking to its partners and Iran in order to be able to find a route forward," Williamson said.
On Monday, the US government re-imposed the first wave of sanctions against Iran that were lifted under the JCPOA. The remaining sanctions will be put back in place on November 4.
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The same day, the countries released statements saying they regretted the re-imposition of sanctions, and the European Union said it would protect any companies in its member-countries who are doing legitimate business in Iran from the US sanctions.
After the United States withdrew from the nuclear deal, the rest of the participants reiterated their commitment.