Iran (search) threatened to reopen its nuclear processing plant here Monday but later agreed to a two-day delay after receiving a request from the head of the U.N. atomic watchdog agency.

Ali Agha Mohammadi, spokesman for Iran's Supreme National Security Council (search), told The Associated Press that International Atomic Energy Agency chief Mohammed ElBaradei (search) asked Tehran for a "maximum of two days" to send its inspectors to Iran's nuclear facility where they can oversee the dismantling of U.N. seals.

But the IAEA denied setting a two-day deadline, saying more time is needed to oversee the plant's resumption of uranium processing, agency spokeswoman Melissa Fleming said.

"We have sent a letter to Iran indicating that it would take at least a week to get our surveillance equipment and other required measures in place," she said.

Earlier, Mohammadi had said Iranian technicians would break the seals and restart nuclear processing on Monday.

Mohammadi said the combination of restraint and resolve toward restarting uranium processing showed the government's intention not to squander Iran's fundamental right to nuclear power, while preserving close ties to Europe.

"Our people were worried that the government may have done a deal with the Europeans and given up the rights of the nation," Mohammadi told the AP. "We will do the rest of the work in coordination with the Europeans."

On state-run TV late Monday, Mohammadi said authorities would delay opening Iran's Isfahan Nuclear Conversion Facility for a week if it thought European negotiators would offer a proposal that left its rights to nuclear technology intact.

Earlier in the day, ElBaradei warned Iran "not to take any action that might prejudice the process at this critical stage."

EU negotiators have said they are mere days from delivering a package of incentives addressing security and political, economic and nuclear issues.

"I also call on Iran not to take any unilateral action that could undermine the agency inspection process at a time when the agency is making steady progress in resolving outstanding issues," ElBaradei said.

Iranian officials had signaled an intensifying impatience with the slow pace of negotiations with Europe, and an incoming conservative administration in Tehran has showed signs of wanting to harden the country's stance.

Mohammadi said authorities still plan to remove the U.N.'s seals on the machinery, in the Isfahan plant, opening the way for the long-stalled conversion of uranium ore concentrate, known as yellowcake, into uranium gas, the feedstock for enrichment.

Iranian officials made clear they were still holding back from restarting most of their suspended program. The country has no plans to reopen the plant in Natanz, where it could begin actual enrichment by injecting uranium gas into centrifuges used to enrich uranium.

Israeli officials warned Monday that unless the international community steps up pressure on Iran, the Islamic state will develop nuclear weapons.

"If the Americans, Europeans and Russians will not take Iran to the (U.N.) Security Council and put real pressure on them, they will produce nuclear capabilities," said Yuval Steinitz, chairman of the parliamentary Foreign Affairs and Defense Committee.

Israel has repeatedly warned that Iran, which already posses a missile capable of carrying a nuclear warhead and reaching Europe, Israel and U.S. forces in the Middle East, is an existential threat to the Jewish state.

In its letter to the International Atomic Energy Agency, the Tehran regime said the EU proposal sought to restrict the country's peaceful development of nuclear power while falling short on economic, technological and nuclear cooperation. It said the EU's "security guarantee" that Iran won't be invaded was also lacking.

Iran's announcement brought sharp responses from European officials who called on the Iranians to respect the terms of the Paris Agreement that meant the nuclear program stayed frozen until negotiations were finished.

Mohammadi said some IAEA inspectors have already arrived in Isfahan. Others are expected to arrive to install more monitoring cameras to record the resumption of work.

U.S. officials claim the Iranian nuclear program is designed to produce weapons. Iran insists electricity is its sole aim. Iran maintains its suspension of uranium enrichment in November was voluntary, giving it the right to resume the activities.

Iran's moves could send it before the United Nations Security Council to face sanctions, as previously called for by the United States.

European diplomats said Sunday that if Isfahan were restarted, an emergency International Atomic Energy Agency board meeting would set a deadline for the Iranians to stop enrichment activities.

If such a deadline were not met, a Security Council referral was a likely next step, the officials said.

Iran's actions could also trigger a short-term economic penalty. The European Union which said Tehran's enrichment steps would damage EU-Iran trade talks.

Germany, which along with Britain and France have been leading U.S.-backed EU negotiations, said Monday that European negotiators still plan to submit their proposal for Iran's atomic program "in a few days."

The proposal, which was delayed a week until Aug. 7, includes nuclear fuel, technology, other aid and "security guarantees" that Iran won't be invaded if it permanently halts uranium enrichment and related activities, European and Iranian officials confirmed.