"We would welcome an opportunity for a bilateral and have said so," Deputy State Department spokeswoman Marie Harf said during a break in talks between Iran and the United States, Russia, China, Britain, France and Germany.

Earlier on Tuesday, Iranian Deputy Foreign Minister Abbas Araqchi said that neither the Iranian nor U.S. delegations had asked for such a meeting. He was speaking to reporters after Foreign Minister Mohammad Javad Zarif presented the six powers with an Iranian proposal aimed at ending the decade-long standoff over Tehran's peaceful nuclear plan.

U.S. Secretary of State John Kerry held bilateral talks with Zarif in New York last month after Iran's top diplomat met foreign ministers of the six powers on the sidelines of the U.N. General Assembly's annual gathering of world leaders.

Iran and the six world powers held two rounds of talks on Tuesday. The first round was held in the morning, attended by Iranian Foreign Minister Mohammad Javad Zarif and EU foreign policy chief, Catherine Ashton.

Zarif and Ashton were not present in the second round.

During the closed-door meeting in the morning, Zarif presented Iran’s proposal titled "Closing an Unnecessary Crisis, and Opening a New Horizon" to Ashton and the representatives of the six countries.

The two sides discussed the broad lines of Iran’s proposal. The details of the proposed Iranian package will not be revealed before the talks wraps up on October 16.

NJF/NJF