"Brave and heroic people of Iran, today JCPOA concluded. I praise God for this great gift and show my utmost respect to you patient people," Rouhani said in a message published on his website.
The International Atomic Energy Agency (IAEA) verified Tehran’s compliance with the JCPOA hours earlier, marking "Implementation Day" and paving a way toward the easing of sanctions imposed on Iran.
"A new chapter opened in relations with [the] world," Rouhani’s message read.
Iran’s Press TV broadcaster quoted him as saying the JCPOA "does not harm any country."
"Iran's friends are happy and its rivals must not be worried. We are not a threat against any government and nation," Rouhani said in a statement.
An estimated $50 billion to $100 billion of Iran’s assets are expected to be unlocked with the nuclear deal.
Critics in Israel and the United States expressed objections to the landmark deal, hailed by leaders including the six world powers who helped negotiated the JCPOA.