The United States on Wednesday welcomed Iran's expected signing this week of the additional protocol to the Nuclear Non-Proliferation Treaty, but said it is only one step toward resolving its nuclear issue. 

"We'd certainly welcome Iran signing of the additional protocol," State Department spokesman Richard Boucher told reporters at a regular press briefing.

"But the signature is only one step toward resolving the remaining open questions about Iran's nuclear program and toward increasing international confidence that Iran's nuclear program will be limited to peaceful activities and that they will truly suspend all uranium enrichment-related and reprocessing activities," he said.

Iranian Vice President Gholamreza Aghazadeh announced Wednesday that his country plans to sign the additional protocol Thursday to allow short-notice inspections of its nuclear facilities by the International Atomic Energy Agency (IAEA).

Iran insists its nuclear program is peaceful and intended only for producing electricity. But in October, it admitted to the International Atomic Energy Agency that it had hidden certain activities from UN nuclear inspectors for 18 years.

Iran has already signed the basic Nuclear Non-Proliferation Treaty. But that treaty allows experts from the UN nuclear agency to carry out inspections only when after receiving permission ahead of time.

(Xinhua News Agency December 18, 2003)