The United Nations nuclear watchdog has begun a new round of talks with Iran in an effort to negotiate a deal allowing the agency to resume an investigation into suspected nuclear weapons research in the Islamic state.

Iran's envoy to the International Atomic Energy Agency met with agency officials Friday in Vienna.

The IAEA wants access to Iran's Parchin military base, where the agency believes Iran has been conducting atomic weapons research. Tehran says Parchin is a conventional weapons facility and insists the Iranian nuclear program is peaceful.

Both sides say progress has been made in previous discussions on the issue this year, although differences remain.

Chinese state media report that President Hu Jintao, who met with his Iranian counterpart Mahmoud Ahmedinejad in Beijing Friday, has urged the Iranian leader to take a flexible and pragmatic approach in the IAEA talks.

A U.S. research organization obtained satellite images last month that indicated Iran may have attempted to destroy traces of nuclear weapons testing at Parchin.