TEHRAN (Dispatches) --President Hassan Rouhani, in an exclusive interview with NBC News, denounced ISIS for its savagery but also branded the U.S.-led coalition against the terror group as "ridiculous”.

Speaking from the presidential premises in Tehran ahead of his visit to the United Nations, Rouhani questioned President Obama’s decision to go after ISIS with airstrikes.

"Are Americans afraid of giving casualties on the ground in Iraq? Are they afraid of their soldiers being killed in the fight they claim is against terrorism?” Rouhani said.

"If they want to use planes and if they want to use unmanned planes so that nobody is injured from the Americans, is it really possible to fight terrorism without any hardship, without any sacrifice? Is it possible to reach a big goal without that? In all regional and international issues, the victorious one is the one who is ready to do sacrifice.

"Maybe it is necessary for airstrikes in some conditions and some circumstances,” he added. "However, airstrikes should take place with the permission of the people of that country and the government of that country.”

Asked about the extremists’ beheading of American James Foley and Steven Sotloff and Briton David Haines, Rouhani said ISIS’ actions are at odds with Islamic tenets.

"They want to kill humanity,” he said. "And from the viewpoint of the Islamic tenets and culture, killing an innocent people equals the killing of the whole humanity. And therefore, the killing and beheading of innocent people in fact is a matter of shame for them and it’s the matter of concern and sorrow for all the human and all the mankind.”

But he also took issue with the American-led coalition, saying members include nations that helped ISIS with weapons and training. He declined to name the countries.

He said Iran will give Iraq any support it requests for combating ISIS, but made a point of saying religious sites must be protected.

"When we say the red line we mean the red line,” Rouhani said. "It means we will not allow Baghdad to be occupied by the terrorists or the religious sites such as Karbala or Najaf be occupied by the terrorists.”

Rouhani also said he believes the nuclear talks can still lead to a resolution. "Maybe the time could be arguable, either today or tomorrow. However, we have no doubt that the only solution to the nuclear issue goes through negotiation,” he said.

He also expressed optimism about Iran’s warming relations with the United States. "The close relationship between the two nations can resolve many problems. A closer contact and relationship would also be beneficial for the American state person, and they can open new ways for the American politicians. We have to look at future more than the past,” he said.

Iran’s foreign minister meanwhile ruled out cooperating with the United States and warned that the terrorist ISIL group poses a much broader global threat that needs new thinking to eradicate.

Muhammad Javad Zarif said Iran has serious doubts about the willingness and ability of the United States to react seriously to the "menace” from ISIL "across the board” and not just pick and choose where to confront it as it has just started doing in Iraq.

"This is a very mobile organization,” he told the Council on Foreign Relations. "This is not a threat against a single community nor a threat against a single region. It was not confined to Syria, nor will it be confined to Iraq. It is a global threat.”

The U.S.-Iranian relationship is at a delicate moment, with a new round of talks on a deal to rein in Iran’s nuclear program set to begin on Thursday, which Zarif said is his top priority. Presidents of the two countries — who talked a year ago — are also arriving next week for the annual ministerial meeting of the UN General Assembly.

Iran was the first country to provide help to neighboring Iraq when ISIL swept across the border from Syria in July. France wanted Iran to attend an international conference in Paris on Monday aimed at coordinating actions to crush the extremists in Iraq but Tehran rejected the request.

Zarif called the 24 participating nations at the Paris conference "a coalition of repenters” because most supported the ISIL group "in one form or another” from its inception following the U.S. invasion of Iraq in 2003.

At the end of the day, he said, they created "a Frankenstein that came to haunt its creators”.

Zarif said Iran’s assistance — without any troops — helped Iraq prevent the ISIL group from taking over Baghdad and Arbil.

Zarif said it’s now time for the international community "and particularly the coalition of the repenters” to stop providing financing, military equipment and safe passage for the group and its fighters.

He didn’t name any coalition members, but Saudi Arabia and Qatar provided financing to the Al-Qaeda breakaway group, and Turkey has not stopped thousands of foreign fighters from crossing into Syria and Iraq to join the ISIL group.

Zarif said the international community must begin to deal with the resentment and disenfranchisement that allows the ISIL group to attract young people from the Middle East to Europe and the United States.

The international community, he said, must also recognize that in a globalized world problems can’t be solved through coercion, exclusion or imposing solutions.

Zarif agreed with U.S. President Barack Obama that the group is neither Islamic nor a state so he referred to it by a previous name, ISIS. But he was critical of the U.S. approach to dealing with the threat from the group.

In Iraq, where the U.S. is carrying out airstrikes, Zarif said, "it will not be eradicated through aerial bombardment”.

In Syria, where the U.S. is beefing up military support for other militants to step up opposition to President Bashar Assad’s government, he said, "you cannot fight ISIS and the government in Damascus together”.

When Zarif was asked what circumstances could lead the two countries to collaborate or even discuss the threat posed by ISIL in Iraq, he said he told U.S. Secretary of State John Kerry that Iran has two fundamental principles — "it should be for the Iraqis to decide and we should not be rewarding terrorists”.

He also implicitly criticized the U.S. for interfering in Iraq’s affairs, saying Iraqis must be allowed to determine their own politics.

"And that was one of the problems we had in the initial approach by the United States, and that is why we turned it down,” Zarif said.