Iran says it is ready for what it calls "serious negotiations" on its nuclear program.
Iran Tuesday presented its formal response to the West's offer of incentives if it suspends uranium enrichment.
Top Iranian negotiator Ali Larijani handed over the reply to envoys representing the five permanent United Nations Security Council members and Germany.
Iranian officials gave no details of the response or say if it specifically mentions uranium enrichment. But they did say Tehran is ready for serious talks.
Monday, Iran's Supreme Leader Ayatollah Ali Khamenei said Iran has already made its decision to continue with its nuclear program. The United States' U.N. Ambassador John Bolton, said Washington will study Iran's formal response carefully.
But he said Washington is ready to move forward with Security Council sanctions if Iran still rejects demands to stop enriching uranium by the council's August 31st deadline.
The United States and many of its European allies say Iran is planning to build nuclear weapons. Iran strongly denies the accusation. It insists its nuclear program is strictly for peaceful energy purposes.
Information for this report is provided by AP, AFP and Reuters.