The International Atomic Energy Agency confirmed it had received a letter from Iran, which Salehi said was submitted on Monday and outlined Tehran's plans.
European powers still back the deal but have concerns over Iran's ballistic missile programme and its influence in the Middle East. Iran says the two issues are non-negotiable.
"If conditions allow, maybe tomorrow night at Natanz (plant), we can announce the opening of the centre for production of new centrifuges", said Vice-President Ali Akbar Salehi, head of the Iranian Atomic Energy Organisation, according to conservative news agency Fars.
Under the 2015 nuclear agreement that Iran signed with world powers, it has the right to build and test certain centrifuges, though detailed restrictions exist for the first 10 years on the types and quantities of the machines.
"What we are doing does not violate the (2015 nuclear) agreement", he said, specifying this was just the start of the production process and "does not mean that we will start assembling the centrifuges".
Salehi also emphasised that these moves "do not mean the negotiations (with Europe) have failed". Iran's nuclear agency said it would inform the United Nations nuclear watchdog on Tuesday the process to increase capacity had begun. "UF6 (uranium hexafluoride). will start on Tuesday".
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Une carte au trésor exclusive pour le mode histoire de Red Dead Redemption 2 pour toute précommande avant le 31 juillet 2018. On ignore cependant si le bonus de GTA$ sera aussi disponible pour toute précommande du jeu sur PlayStation 4.
The announcement came a day after Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei ordered the AOEI to make preparations for enrichment of uranium up to a level of 190,000SWU (separative work unit) without any delay in case of a potential collapse of the Iran deal.
Khamenei on Monday warned European leaders to drop their "dream" of Tehran continuing to curb its nuclear program despite renewed economic sanctions.
On Monday, German Chancellor Angela Merkel defended the Iran nuclear deal in talks with Netanyahu, who is in Europe to persuade its leaders to follow the USA and quit the multilateral accord.
"The EU is willing to use the euro, but the problem is that numerous European companies are unwilling to continue trade with Iran without protection because they have shareholders in the United States or they use the U.S. dollar and they can be punished by the American government", Marandi explained.
The EU also has commercial interests tied up in the deal.
While noting that Iran had stepped up the pressure with its latest announcement, Macron also pointed blame in the direction of US President Donald Trump for unilaterally pulling out of the hard-fought 2015 deal created to stop Tehran getting a nuclear bomb.
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And of course, some iOS apps such as games will make plenty of sense on macOS , while most fitness trackers and camera apps won't. I know as well as anyone, though, that it's hard to watch everyone test the latest and greatest features from the outside.
The three European powers still support the deal. "We are not surprised, we will not allow Iran to obtain nuclear weapons", Netanyahu said in a video statement from Paris, his second stop on a European visit. "I told the prime minister of my deep conviction, which is shared with our European partners, that the accord needs to be preserved to ensure control of nuclear activity", he said.
Before the deal was reached, Tehran enriched uranium to up to 20 percent purity.
Iranian state television broadcast his comments.
Stressing that the Iranian nation and government can not tolerate to be both sanctioned and be put in the "nuclear custody", Ayatollah Khamenei ordered the AEOI to take rapid steps to make preparations for starting uranium enrichment "up to a level of 190,000SWU for the time being within the framework of the JCPOA" and take other preliminary steps that the president has ordered from tomorrow.
Israel itself maintains a policy of nondisclosure with regards to its nuclear capabilities, neither confirming nor denying whether it possessive nuclear arms.
Israel is considered the leading military power in the Middle East and believed to be the only country in the region to possess nuclear weapons.
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Quant à Mohamed Salah , auteur d'une saison exceptionnel avec Liverpool , il est 5e (171.3 millions d'euros). L'été passé, Neymar et Mbappé ont explosé les records de transfert en arrivant au Paris Saint-Germain.