Iran has reportedly halted some activity at its nuclear power plants, setting in motion an interim nuclear deal that promises the country relief from economic sanctions worth $6 billion to $7 billion, in exchange for scaling back its disputed program. 

The deal, which is slated to last for six months, was agreed to by Iran and six global powers, the U.K., U.S., Germany, France, China and Russia, back in mid-November and has been hailed as a historic step towards ensuring that Iran doesn't develop nuclear weapons — an ambition long suspected by world leaders, but denied by the country. Iran insists their nuclear program is for energy purposes only.

Iran's state-run Fars news agency said on Monday that the Iran has halted enriching uranium up to 20 percent and has started to down-blend uranium at higher levels. The 20 percent mark is significant because it is dangerously close to the level of enrichment required for nuclear weaponry, and the fact that Iran has enriched uranium to the high level stokes suspicion that the country is after weaponry, rather than just scientific and medical research as it claims. The IAEA confirmed Fars' report, paving the way for sanctions to lift later today.

Iran has also agreed to allow the U.N. access to its historically secretive program and stop plans to open another nuclear plant. In exchange, the country can continue exporting crude oil at current levels, will be spared new sanctions and see the lifting of ones targeting services, plane parts, petrochemicals, precious metals and services. 

Last week, Reuters reported that Russia and Iran had made a trade deal that would weaken the effect of a Western sanctions lift and potentially harm the nuclear agreement. Any Russia-Iran deal does not appear to have stopped Iran from following through on its commitment, at least for now — but some are unhappy with the terms of the agreement, suggesting that an alternative solution could be sought at a later date. According to the New York Times, criticism of the program from within Iran has been silenced:

Inside Iran, some hard-liners are complaining that the government is trying to silence critics of the deal, which some here say was a loss for the Iranians, who refused any compromise with the West for more than a decade. “Criticizing the Geneva agreement is like denying the Holocaust,” said Hamid Rasaei, a hard-line member of Parliament, according to the semiofficial Fars news agency. His newspaper and another weekly were closed after they spoke out against the agreement, said Mr. Rasaei, a Shiite Muslim cleric. “Anybody who dares to speak out against parts of the agreement will be confronted,” he said. 

Opposition to the deal has come from American politicians as well, according to Al Jazeera:

Threatening to put an end to the deal, however, is a push by US politicians, including some from Obama's own party, to impose new sanctions on the Islamic republic, even though this would contravene the November deal. The pro-sanctions camp believe it has at least 59 votes in the Senate and a healthy majority in the House of Representatives and could be approaching the two-thirds majority needed to override the veto Obama has promised.

And Israeli Prime Minister Benjamin Netanyahu expressed disappointment with the deal back in November, calling it a "historic mistake," and adding, "For years the international community has demanded that Iran cease all uranium enrichment. Now, for the first time, the international community has formally consented that Iran continue its enrichment of uranium." Netanyahu has strongly suggested that he will order military action against Iran if he feels the enemy nation is posing a threat to Israel. 

The deal comes as global leaders dispute the U.N.'s invitation to Iran to attend upcoming Syria peace talks. Iran's commitment to Syrian President Bashar al-Assad has made its spot at the negotiation table controversial in the past and has angered world leaders this time as well, even though some appear to be warming up to Assad.