"Today is the day of the victory of the people of Iran on the political arena," Rouhani said in an address televised on state television. "As of today, it is clear that our country has a big power called the power of diplomacy."
The United Nation’s nuclear watchdog IAEA verified Iran’s compliance with the terms of the Joint Comprehensive Plan of Action (JCPOA) late on Saturday.
The confirmation led to the immediate lifting of UN and EU sanctions, as well as partial sanctions relief by the United States.
"After 12 years of steadfastness and resistance as well as patience and sacrifice…we are at a turning point," Rouhani said, lauding Tehran’s ability to balance national interests and international security in "interacting with the world."
He argued that the milestone now presented Iran’s nuclear program as a "plan for scientific, technological, business and economic cooperation."
The Iranian leader said 1,000 letters of credit were opened on the first day of the so-called Implementation Day outlined by the JCPOA, reached in July 2015.
Up to $100 billion of Iran's foreign assets are expected to be unlocked with the nuclear agreement.