Experts says Washington's contradictory actions won't ease bilateral tensions

The United States on Wednesday extended waivers allowing foreign firms to work at Iranian nuclear facilities without US penalties while hitting Iran's foreign minister with sanctions. A series of contradictory actions will not change the tense situation between the two sides, an expert said.

The US State Department said in a notice sent to Congress that it had extended for 90 days waivers that permit European, Russian and Chinese companies to conduct work at several Iranian civil nuclear sites.

"The action today will help preserve oversight of Iran's civil nuclear program, reduce proliferation risks, constrain Iran's ability to shorten its 'breakout time' to a nuclear weapon, and prevent the regime from reconstituting sites," US State Department spokeswoman Morgan Ortagus said.

The waivers, which were due to expire on Thursday, had been the subject of heated internal debate with Iran hawks opposed to their extension but others arguing that more time was needed to allow companies to wind down their operations, according to The Associated Press.

The exemptions are also the last remaining elements that the US still recognizes from the 2015 Iran nuclear deal from which the US President Donald Trump withdrew last year.

White House National Security Adviser John Bolton described them as "a short 90-day extension" while the US will "watch those nuclear activities very, very closely".

Paradoxically, almost at the same time, the US announced new sanctions against Iranian Foreign Minister Mohammad Javad Zarif.

The sanctions freeze any of Zarif's assets in the US or that are controlled by US entities, the government announced, saying it also will curtail his international travel, according to Agence France-Presse.

"The United States is sending a clear message to the Iranian regime that its recent behavior is completely unacceptable," Treasury Secretary Steven Mnuchin said.

Zarif responded through his social media account that the reason for designating him is that he is Iran's "primary spokesperson around the world" and reiterated that the move "has no effect" on him or his family as they "have no property or interests outside of Iran".

Iranian President Hassan Rouhani on Thursday slammed US financial sanctions on Zarif.

"They have started doing childish things," Rouhani said in a speech.

"Every day they claim: 'We want to negotiate with Iran, without any preconditions' and then they put sanctions on the country's foreign minister."

Tao Wenzhao, a Chinese senior researcher on US studies, said the US is playing a two-track strategy of trick-and-treat with Iran.

He said the extension could to some extent help Iran alleviate domestic economic problems, and is also a step Washington has to take when considering the benefits of its alliances.

"If the US completely bans Iran's oil trade, the outcome will not only harm Iran but also US allies as they are main buyers of Iran's oil or need to ship oil through the Strait of Hormuz."

Meanwhile, the sanctions, although they have no substantial effect, is a posture Trump gives to show his determination of pressing Iran, Tao said.

"Zarif has no assets in the US while the sanctions can't inhibit his travels to New York for official United Nations business next month," he said. "But whether useful or not, the move indicates that Washington is still pressing Teheran."

Tao also said the series of actions will not have a substantial impact on the tense situation between the US and Iran.