Iran's top security body called Saturday for unity on the country's nuclear policy following a public row between the government and parliament over a controversial bill.

The bill "for the lifting of sanctions and protection of the Iranian people's interests" was approved by the powerful Guardian Council on Wednesday and has to be signed by President Hassan Rouhani to become law.

Having drawn heated opposition from the government, the bill calls on the administration to end UN inspections of Iran's nuclear facilities and to "produce and store 120 kilogrammes (265 pounds) per year of uranium enriched to 20 percent".

Both steps would run counter to commitments made by Tehran in a landmark deal with major powers in 2015 and would likely complicate efforts to get Washington back on board after outgoing US President Donald Trump abandoned it in 2018.

In a statement published by Iranian media on Saturday, the supreme national security council said that the bill "does not produce any specific issue for national interests".

"In contrast, what is against national interests and a cause for concern is this ruckus which has damaged the position and status of the country's legal bodies," it said.

The body condemned "recent remarks and attitudes" which have "sacrified national for partisan interests, have no benefit for the country and send the wrong message" to Iran's foes.

It called on authorities to focus on "reinforcing national unity" and vowed to prevent Iran's interests becoming "a plaything in the hands of politicians".

Passage of the bill, which was first drafted in early November, was speeded up following the assassination of Iran's top nuclear scientist Mohsen Fakhrizadeh.

He was killed on a major road outside Tehran last week in a bomb and gun attack that Iran has blamed on its arch foe Israel.

The security council statement came after Rouhani and parliament speaker Mohammad-Bagher Ghalibaf exchanged sharp remarks in a public dispute in recent days.

On Wednesday, the president called the bill "detrimental to the course of diplomatic activities."

Rouhani's government has signalled a readiness to engage with US President-elect Joe Biden after four tense years under  Trump, who reimposed crippling sanctions after withdrawing the United States from the nuclear agreement.