MOSCOW, January 13. /TASS/. Russia will explain persistently to the U.S. the depravity and viciousness of its sanctions-based policies against Iran and the DPRK, Russia’s Deputy Foreign Minister Sergei Ryabkov told TASS on Saturday.

"Here is the border between the U.S. illegal approach to international problems and the actions in line with mutual respect for sovereignty, which we follow," he said in a comment on the sanctions pressure from the U.S. on Iran and North Korea. "We shall explain persistently to the U.S. the depravity and viciousness of their line."

"But, once again, after yesterday’s statements future of the Joint Comprehensive Plan of Action [on the Iranian nuclear program] is under a big question," he added.

The U.S. possible decision to quit the nuclear deal with Iran will affect strengthening of the non-proliferation regime, the diplomat said, while commenting on a recent statement by the U.S. President Donald Trump.

"The ultimatum-like character of yesterday’s signals from Washington, most likely, is based on the U.S’. decision to head for quitting the Joint Comprehensive Plan of Action," he said. "The U.S. possible quitting the Iranian deal will affect greatly the entire system of international agreements and strengthening of the nuclear non-proliferation regime."

In case the decision is implemented, it will "affect greatly the international situation, the regional affairs, and will affect the system of multilateral agreements and further strengthening of the international regime of non-proliferation," the deputy foreign minister said.

"If it means in May the new certification of Iran’s complying with the Joint Comprehensive Plan of Action will not happen - which is how we read yesterday’s signals [from Washington] - then here we clearly see a classical ultimatum from the U.S. side," he said. "Using ultimatums is clearly impossible in diplomatic work and in settling realistic problems, and the Americans could have realized it."

On Friday, Trump said the United States would withdraw from the Iranian nuclear deal unless its "disastrous flaws" were fixed. The U.S. leader decided to waive nuclear sanctions against Iran "but only in order to secure our European allies' agreement to fix the terrible flaws of the Iran nuclear deal,"

The deal on Iran’s nuclear program was reached between Iran and six international mediators (the United Kingdom, Germany, China, Russia, the United States, and France) on July 14, 2015. Under the deal, Iran undertakes to curb its nuclear activities and place them under total control of the International Atomic Energy Agency (IAEA) in exchange of abandonment of the sanctions imposed previously by the United Nations Security Council, the European Union and the United States over its nuclear program.

After Tehran had implemented its part of the deal, which was confirmed during IAEA’s inspection trips, on January 16, 2016 the U.S. administration under President Barack Obama lifted sanctions imposed on Iran over its nuclear program. Nevertheless, many other restrictions, for instance over Iranian ballistic missiles, remained in place. On October 13, 2017, the U.S. current President Donald Trump refused to confirm Iran was implementing the nuclear deal.