UN Secretary-General Kofi Annan urged on Friday the United States to come back to the negotiation table and hold "direct" talks with Iran over the nuclear issue.

"Negotiation is the best solution," Annan told a press conference at the interval of the EU-Latin America summit, being held in Vienna.

When asked whether he requested the U.S. to have "direct links" with Iran over the nuclear issue, Annan said he have asked both sides in both "private and public" channel to come to the negotiation table.

Since the Iran nuclear issue emerged, the United States has refused to conduct direct talks with Iran, even repeatedly warned of not excluding military strike against Iran.

Annan said that the United States should join the European Union (EU) and Iran to find a solution.

He also urged all sides to be "open", and to "intensify their efforts" to come out with a "comprehensive package" for resolving the Iran nuclear issue.

Source: Xinhua