(MENAFN- Qatar News Agency) Iran and the P5+1 group agreed Wednesday to convene a new round of the nuclear talks here on April 7-9. In a joint statement following a closed-door meeting, EU foreign policy chief Catherine Ashton, Iranian Foreign Minister Mohammad Javad Zarif, and representatives of the six world powers (Britain, China, France, Germany, Russia and the United States) hailed as substantive and useful today's meeting. The discussions covered, inter alia, the uranium enrichment at the Iranian Arak reactor, civil nuclear cooperation and the international sanctions on Iran, according to the statement. The statement said the coming round of talks will discuss key relating to a final comprehensive deal on Iran's nuclear progra