US President Barack Obama on Thursday called on Iran to seize the opportunity of nuclear talks to open a "new chapter in the history".

"There is a chance to reach an agreement if Iran takes meaningful and verifiable steps to assure the world that its nuclear program is for peaceful purposes only," Obama said in a video message marking Nowruz, the Persian new year.

If Iran seizes the opportunity, Obama said, it could open up new "possibilities and prosperity" for the Iranian people for years to come.

Obama, however, acknowledged that the process to a comprehensive nuclear deal would be "difficult" and he was "under no illusions."

"I'm committed to diplomacy because I believe there is the basis for a practical solution," he added.

Talks between Iran and Britain, China, France, Russia and the United States plus Germany, the P5+1, took place in Vienna, Austria, from Tuesday to Thursday. The talks were heading to a comprehensive deal to resolve Tehran's long standing disputed nuclear program.

Iran and the six powers agreed that the next round of talks would reconvene on May 7 in Vienna, which would continue to discuss tough issues.