US President Barack Obama offered holiday greetings to Iranians celebrating the first Nowruz, or new year, since a landmark nuclear deal, and welcomed "a chance for a different future" between the two countries.

US President Barack Obama offered holiday greetings to Iranians celebrating the first Nowruz, or new year, since a landmark nuclear deal, and welcomed "a chance for a different future" between the two countries.

"Every year as president I've taken this opportunity, the hope of spring, to speak directly with the people of Iran about how we might open a new window and begin a new relationship with our countries," Obama said Saturday in a video message to the Iranian people, posted online one day ahead of Nowruz.

"Now, for the first time in decades, there's a chance for a different future."

Tehran and six world powers, including the United States, agreed to the deal in July when Iran promised to scale down its nuclear activities in return for the lifting of UN and Western sanctions, including on its oil exports. The Nowruz holiday comes just two months after implementation of the deal began.

"The nuclear deal was never intended to resolve all the disputes between our two nations, and the United States continues to have profound differences with the Iranian government," Obama said.

"But even as our two governments continue to have serious disagreements, the fact that we are now talking to each other on a regular basis, for the first time in decades, gives us an opportunity, a window, to resolve other issues."

"As we do, I firmly believe we can continue to expand the connections between the American and Iranian people," Obama added.

Washington cut diplomatic ties with Iran in 1979, when its embassy in Tehran was stormed by university students, months after the victory of the Islamic Revolution led by Grand Ayatollah Rohullah Al-Khomeini.