The US intensified its pressures against the Iranian nation recently by refusing to reissue sanctions waivers on Iranian oil sales followed by a Friday announcement that it would try to force Iran to stop nuclear enrichment in a blatant violation of the nuclear deal.
"We have mobilized all of the country's resources and are selling oil in the "grey market", state news agency IRNA quoted Zamaninia as saying.
The United States also scrapped its sanctions waiver that had allowed Iran to evade a 300-kg limit on the amount of low-enriched uranium it can store under the nuclear deal at its main nuclear facility of Natanz.
Besides, Iran would no longer be able to ship additional heavy water produced at its Arak facility to Oman for storage. Washington re-imposed sanctions on nuclear cooperation with Iran, including by re-designating Atomic Energy Organization of Iran entities, and by placing new limits on foreign assistance that could expand Iran's nuclear program in November 2018. "This includes denying Iran any pathway to a nuclear weapon", State Department spokeswoman Morgan Ortagus said.
They also said they were concerned by the USA decision "not to fully renew waivers for nuclear non-proliferation projects in the framework of the JCPOA [Joint Comprehensive Plan of Action]" - the title of the nuclear deal. The Fars agency carried a similar report.
"We encourage all countries, including Russian Federation and China as JCPOA participants, to make their best efforts to pursue the legitimate trade that the agreement allows for, through concrete steps", they added.More news: Warren Buffett's Berkshire Hathaway invests in Amazon for the first time
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"We certainly won't sell 2.5 million barrels per day as under the (nuclear deal)", Zamaninia said, giving no figures for current sales.
Mahjoob Zweiri, director of the Gulf Studies Center at Qatar University, told Al Jazeera the USA move is aimed at stopping Iran from exporting oil.
"It aims at having a positive impact not only on trade and economic relations with Iran, but most importantly on the lives of the Iranian people", the statement added. "So we have to increase our hard currency income and cut our currency expenditures", Mr Rouhani said.
Friday's development comes after the administration's decision to end waivers that allowed countries, including India, to import Iranian oil on May 2.
The Trump administration also took the unprecedented step of designating Iran's Revolutionary Guard Corps as a foreign terrorist organization.