The top foreign adviser to Iran's supreme leader, Ayatollah Ali Khamenei, has called for new direct talks with the United States amid the multilateral negotiations over Iran's nuclear program.

The remarks Friday by Ali Akbar Velayati signaled a high-level endorsement of the policies of President Hassan Rohani, whom hard-liners have criticized over last month's nuclear deal and other contacts with the U.S.

Velayati said Iran should talk separately with each of the "5+1" powers, which include the United States. "We aren't on the right path if we don't have one-on-one talks with the six countries," he said, according to the semi-official Mehr news agency.

One of Iran's senior negotiators, Abbas Araghchi, said experts from Iran and the world powers will hold a new round of talks Monday on implementing last month's deal.