The delegations of P5+1 countries and Iran, headed by political directors, gathered in Vienna Wednesday for another round of talks over Tehran's nuclear program as an end of June deadline looms, Sputnik reported.

The deadline for the final deal on Iran’s nuclear energy program is set for June 30, 2015.

The delegations will hold several bilateral meetings at Vienna's Palais Coburg hotel, a coordination meeting without Iran and a plenary meeting with the Iranian delegation.

The delegations of France, United Kingdom, China, Germany and Russia are already at the Coburg hotel.

The world powers and Tehran are expected to work out the details of a final agreement ensuring the peaceful nature of Iran's nuclear program in exchange for easing of sanctions.

On April 2, the P5+1 negotiators and Tehran reached a political framework agreement on the Iranian nuclear program in the Swiss city of Lausanne.