Iranian Foreign Minister Mohammad Javad Zarif has accused Saudi Arabia of "actively" backing terrorist groups in western and eastern Iran.
"The claim of forming a coalition against Daesh is a lie; of course, Americans are against 'an uncontained Daesh, ' but if anyone would want to truly destroy Daesh, they [Americans] will counter them", he said, using an Arabic acronym for the group.
Also on Tuesday, Ali Akbar Velayati, a senior adviser to Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei, reacted to Jubeir's remarks, saying the comments by "inexperienced" Saudi diplomats against the Islamic Republic showed their ignorance about Iran and the region, stressing that Tehran would never tolerate Riyadh's warmongering policies.
"The United States and the Israeli regime backed the Daesh terrorists who carried out dual attacks on Iran's parliament and Imam Khomeini's shrine", Jafari told the media.
Several suspected militants, including the alleged mastermind of twin attacks in Tehran last week, were tracked down, detained or killed by Iranian authorities, a security official and a minister confirmed.
The Iranian Revolutionary Guards blamed Saudi Arabia, its Sunni rival in the region, for the attack.
"America's claim of fighting against Islamic State is a lie".
The pragmatist president championed a nuclear deal with the United States and five other powers in 2015 that led to the lifting of most sanctions against Iran, in return for curbs on its nuclear program. The assurances came a week after Iran suffered its first deadly terrorist attack in many years.
Zarif told the forum that recent Saudi officials' remarks against Iran are a "direct threat and very risky provocation".
The terrorist acts included the assassination of high-profile Iranian officials as well as the killing of ordinary citizens, he said.
Saudi Arabia, the United Arab Emirates and Bahrain broke off relations with Qatar on 5 June, accusing the small but oil-rich emirate of supporting "terrorism" and being too close to Iran, which is Riyadh's regional rival. He propagated the conspiracy theory that the US wishes to prop up the extremist group to further instability in the region.
The Oslo Forum is an annual two-day conference on ways to promote global peace attended by armed conflict mediators and peace process actors. On Friday, however, he turned his wrath for the attacks on the United States and Saudi Arabia.