Iranian lawmakers have approved a bill to suspend United Nations inspections of the country's nuclear facilities and boost its uranium enrichment if the remaining signatories to the 2015 nuclear deal do not provide relief from sanctions.

The parliament, which is led by hard-liners, passed the legislation on December 1 in what was seen a show of defiance days after the killing of a prominent Iranian nuclear scientist.

'Death to America! Death to Israel!' lawmakers chanted after passing a draft of the bill, which requires approval by the Guardians Council, a constitutional watchdog.

State TV quoted Parliamentary Speaker Mohmmad Baqer Ghalibaf as saying lawmakers were 'hopeful for the removal of sanctions through this stern decision."

However, government spokesman Ali Rabiei quickly warned that the move would not change Iran's nuclear policy, describing it as a prerogative of the Supreme National Security Council.

"Nobody can work on it independently,' Rabiei said.

The United States unilaterally withdrew from the nuclear agreement between Tehran and world powers in 2018, and started imposing crippling sanctions on Iran.

In response, Iran has breached provisions of the deal, which scrapped sanctions in return for curbs to the country's nuclear program.

However, inspectors of the UN nuclear watchdog, the International Atomic Energy Agency (IAEA), continue to monitor Iranian nuclear sites as part of the 2015 pact.

SEE ALSO: UN Watchdog Says Iran Has Again Breached Nuclear Deal With Step To Fire Up Centrifuges

The bill requires the Iranian government to suspend IAEA inspections if Western powers that are still signatories to the 2015 nuclear accord -- Britain, France, Germany, China, and Russia -- do not reestablish Iran's access to world banking and oil markets within a month.

It also calls for Iran to resume enriching uranium to 20 percent purity 'for peaceful uses.'

Iran currently enriches a growing uranium stockpile up to around 4.5 percent, above the deal's 3.67 percent cap, but below the 20 percent Iran had achieved before and the 90 percent purity considered weapons-grade.

Tehran has always denied pursuing nuclear weapons, saying its nuclear program was strictly for civilian purposes.

The bill was first tabled in parliament in August but gained new momentum after the killing of Mohsen Fakhrizadeh, who was at the heart of the country's past covert nuclear program, on the outskirts of Tehran on November 27.

SEE ALSO: Iran's Security Apparatus Under Fire After Top Nuclear Scientist Assassinated

Iranian authorities have blamed the killing on Israel.

Israeli officials have declined to comment on the killing, and no one has claimed responsibility.

With reporting by AP and Reuters

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