"These calls are being voiced in a rather recurrent way, I would even say, on a regular basis. We do not know what in the JCPOA could have dissatisfied the US side. The content of the document is well-known and the US side monitors its implementation and participates in the sessions of the Joint Commission [of the JCPOA], as well as in other discussions," Ryabkov said commenting on Pence's statement.
According to the Russian diplomat, the attempts to step up pressure on Tehran over reasons not related to the Iranian nuclear agreement would be "a dirty game."
"If a pretext for stepping up pressure against Iran is being looked for over reasons unrelated to the JCPOA, and it is true, according to our observations, then it is a dirty game, which is at the odds with the status of a great power," the diplomat added.
Speaking about the recent US decision to put five Iran-based companies on the sanctions list and the potential introduction of new sanctions, Ryabkov said that Washington's claims against Tehran regarding its regional policy were not entirely clear, adding that if someone was dissatisfied with Iran's foreign policy then it was necessary to enhance dialogue with the country and use diplomatic means in order to settle any issues.
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At the same time, Russia sees no reason to make changes in the provisions of the JCPOA.
"We do not see any reasons to somehow amend the JCPOA. The accord is thoroughly balanced, it is well-considered and each provision of the deal has a logical basis behind it," Ryabkov said.
The statements come after US Vice President Mike Pence said Wednesday that Washington was supportive of having "a long-term agreement" on the Iranian nuclear program and within the framework of this deal if Tehran made an attempt to obtain nuclear weapons or ballistic missiles, all the anti-Iran sanctions would be "re-imposed immediately."