Iran's Guardian Council of Constitution, the highest legislative body of the country, on Wednesday approved a parliament's bill which urges suspension of UN inspections of Iran's nuclear facilities if signatories of the 2015 nuclear deal do not take steps to remove U.S. sanctions against Iran. 
  
Abbas Ali Kadkhodaei, spokesman for the Guardian Council, was quoted by Iran Press news website as saying that the council "did not consider this plan against the constitution and approved it."  

In retaliation for the killing last week of Iran's top nuclear scientist Mohsen Fakhrizadeh, which Tehran has blamed on Israel, Iran's hardline-dominated parliament on Tuesday approved the bill with a strong majority that will harden Iran's nuclear stance. 

The bill urges the administration of President Hassan Rouhani to stop UN nuclear watchdog's inspections of the country's nuclear facilities, which Iran had accepted under the Additional Protocol document subject to the 2015 nuclear deal. 
  
After being approved by the Guardian Council, the bill turned into a law which mandates the government to halt the voluntary implementation of the Additional Protocol document in case signatory states of the nuclear deal do not take steps to "normalize banking relations and completely remove barriers for exporting Iran's oil" in two months. 

The Guardian Council is charged with ensuring draft laws do not contradict Shi'ite Islamic laws or Iran's constitution.

Under the new law, Tehran would give two months to the deal's European parties to ease sanctions on Iran's oil and financial sectors, imposed after Washington quit the pact between Tehran and six powers in 2018. Iran's government should also resume uranium enrichment to 20 percent and install advanced centrifuges at its Natanz and Fordow nuclear facilities. 
  
However, Rouhani criticized the parliament's bill earlier on Wednesday, official IRNA news agency reported. 
  
"The government does not agree with the bill passed by the parliament yesterday," Rouhani said, adding that "it (the bill) would be detrimental to diplomatic efforts." 

The stance of Supreme Leader Ayatollah Ali Khamenei, who has the last word on all matters of state, is not known.

Hard for Biden to rejoin Iran nuclear deal

In reaction to U.S. President Donald Trump's "maximum pressure" policy on Tehran, Iran has gradually reduced its compliance with the deal. 

The law pushed by hardline lawmakers would make it harder for U.S. President-elect Joe Biden, who will take office on January 20, to rejoin the agreement. 

Biden has said he would return to the pact and would lift sanctions if Tehran returned to "strict compliance with the nuclear deal." 

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"There's now more pressure on (President Hassan) Rouhani's government to secure a U.S. return to the JCPOA (the Joint Comprehensive Plan of Action) quickly," tweeted Ariane Tabatabai, a Middle East researcher at the German Marshall Fund and Columbia University. 

In his most substantive remarks on Iran since his victory, Biden told The New York Times that he still backed the 2015 deal in an interview with columnist Thomas Friedman published Wednesday. 

The top US priority should be to prevent an Iranian nuclear weapon, Biden said, explaining, "The last goddamn thing we need in that part of the world is a buildup of nuclear capability."  

After re-entering the agreement, "in consultation with our allies and partners, we're going to engage in negotiations and follow-on agreements to tighten and lengthen Iran's nuclear constraints, as well as address the missile program," he said.  

(With input from agencies)