Vienna – International powers that agreed to resume nuclear talks with Tehran reaffirmed their support for “a diplomatic solution to the Iranian nuclear issue and readiness to restart dialogue with Iran” on Thursday, CNN informs.“We call on Iran to enter, without pre-conditions, into a sustained process of serious dialogue, which will produce concrete results,” Germany and the five permanent members of the U.N. Security Council – China, France, Russia, Great Britain and the United States – said in a statement.“We reaffirm that our overall goal remains a comprehensive negotiated, long-term solution, on the basis of reciprocity and a step-by-step approach, which restores international confidence in the exclusively peaceful nature of Iran’s nuclear program consistent” with the Nuclear Non-Proliferation Treaty.The proposed talks come after Iran signaled a willingness to let U.N. inspectors visit a military base that some suspect is involved in the development of nuclear weapons, a move that could possibly ratchet down rising tensions between Iran, Israel and the West.Israel, the United States and other countries have long said they suspect Iran is trying to build nuclear weapons, and international inspectors have voiced concern about the possibility. Iran has insisted that its nuclear program is for peaceful purposes. In their statement, the world powers expressed regret about uranium enrichment activities at the Fordow and Natanz facilities. Iran confirmed this year that it began the enrichment of uranium at its underground Fordow facility, and reports emerged last month that new advanced centrifuges were being used at Natanz.The nations – collectively known as the P5 plus 1 – noted that the International Atomic Energy Agency, the U.N. nuclear watchdog, “held two rounds of talks in Tehran in January and February 2012, and during these rounds an intensive discussion was held on a structured approach to the clarification of all outstanding issues.” “We are concerned that, despite efforts made so far, no agreement was reached, including on the access to relevant sites in Iran, requested by the Agency. In that context, we urge Iran to fulfill its undertaking to grant access” to the Parchin military base.