Iranian President Hassan Rouhani on Thursday blamed efforts to combat terror in response to the Sept. 11 attacks for only widening the spread of global extremism and accused regional rival Saudi Arabia of flooding the Middle East with “hateful ideology.” But in an otherwise somber speech, he cited Tehran’s nuclear deal as an example of how diplomacy can resolve conflicts that could spiral into war.

While touching on familiar topics, Rouhani’s comments to the U.N. General Assembly were notable in pulling few punches at a forum where many other speeches have generally been moderate in tone.

Although Rouhani refrained from criticizing the United States by name, he placed the blame for the spread of extremism on the responses by “great powers” to the Sept. 11 attacks. Rouhani said they led to a more insecure world by “advancing different methods of repression and military intervention under the pretext of creating a secure environment for their citizens.”

Rouhani also was critical of a U.S. Supreme Court ruling this year allowing families of victims of bombing attacks that Washington says were linked to Iran to allow monetary damages from that country. At risk for Tehran is 1.75 billion in bonds, plus accumulating interest.

But he was most tough on Saudi Arabia. Bitter rivals, Sunni Saudi Arabia and Shiite Iran are on different sides in the Syrian conflict as well as fighting proxy wars in Yemen where Houthi rebels are fighting government forces. Traditional tensions have been exacerbated by last year’s crush and stampede during the annual pilgrimage to Sunni holy sites. Thousands of Iranian pilgrims died and Tehran says poor organization of the event by the desert kingdom is to blame.

Rouhani urged the Saudis to “compensate for past mistakes.” Riyadh, he said, “must cease and desist from divisive policies, spread of hate ideology and trampling upon the rights of neighbors,” while accepting “responsibility for the protection of the lives and dignity of pilgrims. ”

Since its implementation in January, the nuclear agreement between Iran and six world powers has received generally positive reviews both from Tehran and the United States, the lead negotiator with Tehran. They have also contributed to tamping down tensions between Washington and Tehran, and Rouhani on Thursday invoked the pact as “indicative of the success that we could achieve through moderation, constructive interaction and the promotion of dialogue.”

At the same time, he bemoaned “the lack of compliance” by Washington. Iran complains that international financial sanctions are not being lifted quickly enough under the agreement that stipulates a removal of these and other penalties imposed over Tehran’s nuclear program in exchange for Tehran’s agreement to curb atomic activities that could be used to make a bomb.

(AP)