Iran will start implementing the nuclear deal it signed with world powers within the next two to three weeks, according to the country's President Hassan Rouhani, in a move seen by analysts as a major political victory for the reformist leader ahead of two crucial elections.

The UN nuclear agency's decision to end the investigation into the long-running allegations that Tehran was working on a nuclear weapons programme was called a "big victory" by Rouhani in a a televised address on Wednesday.

On Tuesday, Yukiya Amano, director general of the International Atomic Energy Agency (IAEA), said during a meeting in Vienna that there were "no credible indications" of a development of "a nuclear explosive device after 2009".

Iran nuclear deal: How both sides are telling the story

Amano added that the agency had not found "any credible indications of the diversion of nuclear material in connection with the possible military dimensions to Iran’s nuclear programme".

That prompted Rouhani's high-profile speech where he also declared that his government "has unshackled the sanctions from our economy".

"I now tell the nation that, by early January 2016, all sanctions will be eliminated and the path to our improved interaction with the world will be wider and safer," Rouhani said.

Ariane Tabatabai, an Iran expert at Georgetown University in Washington DC, said that for years hardliners in Iranian politics have been arguing against the negotiations as well as the deal, and they have been outmanoeuvred by Rouhani.

"This was a big win for Rouhani," Tabatabai told Al Jazeera. "This is also a key step in re-establishing Iranian confidence in the IAEA's neutrality and credibility, which hardliners had spent years undermining."

Iran's Supreme Leader Ayatollah Ali Khamenei had made the closure of the IAEA investigation, as one of the pre-conditions for his support of the deal, and for Iran to carry out its part of the bargain, including the reduction of uranium-enriching centrifuges from 19,000 to just a third of it at around 6,100.

Rouhani's speech came a day ahead of the December 17 start of the filing of candidacy for the Assembly of Experts election on February 26.

The elected 86-seat body is in charge of selecting the country's supreme leader. Voting takes place every eight years.


In Photos: Iranians take to Tehran streets to hail nuclear deal


Rouhani, as well as another former president, Akbar Hashemi Rafsanjani, is expected to take part in the election which coincides with the parliamentary elections. 

Both are crucial, and the timing of Rouhani's speech could not have happened at a better time, Tabatabai said. 

"This is great timing for Rouhani to be sure. Whether or not it'll actually influence the course of the elections is a different story," she said. 

Rohollah Faghihi, an expert in Iranian politics and a journalist with the Tehran-based website Entekhab, said that with the speech, Rouhani sought to remind people "that it was his moderate and benign diplomacy that led to the end" of the nuclear sanctions.

"The election date is near and Rouhani didn't want people to forget his government's achievements," Faghihi told Al Jazeera before adding that the hardliners were still complaining about the nuclear deal and how the investigation of the possible military dimensions of Iran's nuclear programme was closed.

"The president asked them not to slam and devalue this deal because everything is now over."

Iran accused of violating UN missile ban

Tabatabai said that Iranian hardliners are "unlikely" to try and sabotage the implementation of the nuclear deal "by taking measures directly in violation" of the July agreement.

"They have, and are likely to take the fight further into the realm of intercontinental ballistic missile tests, cyber attacks and domestic pressure in the next few months," she warned.

"That way, they can remind Rouhani that he may have won a battle but not the war, and put more obstacles on the way during implementation."

Meanwhile, speaking to Al Jazeera's Jane Dutton earlier on Wednesday, Mohammad Marandi, dean of world studies at University of Tehran, warned that any new sanctions against Iran would threaten the nuclear deal.

Marandi was reacting to the US proposal for possible sanctions, after reports emerged that Iran had violated a UN Security Council resolution in October, when it test-fired the medium-range Emad rocket.

"If there are further sanctions, then that would jeopardise the [nuclear] agreement," he said, adding that Iran would not accept limits on conventional defence.

Source: Al Jazeera