Iranian President Hassan Rouhani addressed attendees during the 70th session of the United Nations General Assembly at the U.N. headquarters in New York, Sept. 28, 2015. REUTERS/Carlo Allegri

The Iran nuclear deal recently reached by the U.S., Iran and five other world powers, paves the way for cooperation in the region, Iranian President Hassan Rouhani said Monday at the United Nations. The agreement provided a model for how countries could avoid war while also working for mutual gain. At the same time during his address to the U.N. General Assembly, Rouhani touched on critical areas in which Iranian and U.S. policy disagree in the region, namely over the protracted war in Syria.

"From the standpoint of international law, this instrument sets a strong precedent where for the first time, two sides, rather than negotiating peace after war, engaged in dialogue and understanding before the eruption of conflict," Rouhani said.

The leader hinted at the idea the U.S. and Iran, as well as other countries, could see improved relations in the future. At the same time, significant disagreements exist, as Iran continues to view U.S. involvement in the region as a source of conflict.

"I say to all nations and all governments that we will not forget the past, but we do not wish to live in the past. We will not forget war and sanctions, but we look to peace and development," he said.

“We are prepared to assist in eradication of terrorism. We are prepared to help bring democracy to Syria, Yemen,” Rouhani said, noting that the country has stepped up its fight against Islamic militant groups in Syria.

The U.S. and Iran have seen tensions escalate over the military situation in Syria. Though they agree on the importance of defeating the Islamic State group in Syria, also known as ISIS or ISIL, the U.S. has insisted Syrian President Bashar Assad's removal from power is necessary to a peaceful transition of power in Syria, Iran has said Assad is crucial to the fight against ISIS. Iran has been a longtime ally and financial backer of the Syrian president's regime.

"We support the consolidation of power through the vote of people rather than through arms. We defend the rule of the majority that respects the rights of minorities," Rouhani said, as he also defended Syria's right to national sovereignty, a critique of international intervention in the country.

The nuclear deal, reached by Iran, the U.S. and five other world powers, will see crippling sanctions against Iran lifted in exchange for a commitment from the Islamic Republic to end its nuclear program. The agreement has come under scrutiny by hard-liners in both countries. While Congressional Republicans have said Iran cannot be trusted to abide by the terms of an agreement, some Iranians have criticized the agreement as bowing to American pressure. The deal is believed to have general support among the Iranian public, and has also been supported by Iran’s supreme leader, Ayatollah Ali Khameini.

"This opportunity can be seized in order to look to the future and avoid focusing on the past and rebuild our relationships," Rouhani said Monday.

Obama reiterated during his U.N. speech Monday morning any long-term solution in Syria must involve the removal of both ISIS and Assad.

"There cannot be a return to the prewar status quo," Obama told the General Assembly. "Let's remember how this started: Assad reacted to peaceful protests by escalating repression and killing and in turn created the environment for the current strife."