"The Islamic republic of Iran has presented a new proposal that includes concrete actions, and we foresee that the text will be finalised on Monday and that the two sides will reach agreement," Reza Najafi told state television.
"Mr (Yukiya) Amano has accepted Iran's invitation and will arrive in Tehran on Monday morning."
The International Atomic Energy Agency confirmed on Friday that its chief has accepted an invitation to visit Iran, raising hopes for a long-stalled probe into Tehran's suspected past bomb-making efforts as tough talks continued in Geneva on its current nuclear programme.
Amano "will travel to Tehran on 10 November to meet senior Iranian leaders on Monday, 11 November, with the aim of strengthening dialogue and cooperation," the IAEA said.
"Separately, as previously announced, IAEA and Iranian experts will meet in Tehran on Monday to discuss technical issues," the Vienna-based body said in a statement.
It will be Amano's second trip to Tehran, after he visited in May last year. On his return to Vienna he announced that a deal was imminent, but it did not happen.
The announcement of his latest visit came as six world powers held a second day of negotiations with Iran in Geneva on easing the long-running standoff over Tehran's nuclear programme.
The IAEA conducts regular inspections of Iran's nuclear facilities but it also wants to investigate possible efforts before 2003, and maybe since, to develop a nuclear weapon.
Iran's separate talks with the United States, China, Russia, Britain, France and Germany, known as the P5+1, are focused more on Tehran's current activities, in particular uranium enrichment.
Iran rejects the IAEA's weaponisation claims, and says that they are based on faulty intelligence from the likes of the CIA and Israel's Mossad that it complains it has not even been allowed to see.
For two years, since the IAEA published a major report on the allegations in November 2011, talks between Iran and the agency have failed, including during Amano's high-profile visit 18 months ago.
The separate Geneva talks were entering a previously unscheduled third day Saturday amid mounting speculation of a deal in the offing, despite major obstacles remaining.
US Secretary of State John Kerry curtailed a Middle East tour to attend the talks, joining his British, French and German counterparts who converged on Geneva on Friday. Russia's top diplomat flew in to join them Saturday.