The head of the U.N. nuclear agency has urged Iran to again suspend its uranium enrichment activities, although Tehran vowed to continue with the process.
A spokeswoman for the International Atomic Energy Agency says Mohamed ElBaradei made his request in talks on Thursday in Tehran with the head of Iran's atomic energy organization Gholamreza Aghazadeh.
ElBaradei later said he has not yet confirmed that Iran has enriched uranium to a level used in nuclear power plants -- a breakthrough Tehran announced Tuesday.
In Washington, U.S. Secretary of State Condoleezza Rice said the U.S. plans to look at a full range of options available to the U.N. Security Council to address Iran's defiance of council resolutions.
She said one of the options is the ability to compel Iran under chapter seven of the U.N. charter, which could allow for sanctions.
ElBaradei is to report on Iran to the Security Council on April 28th -- the deadline the council has set for Tehran to halt its nuclear activities.
The United States accuses Iran of running a secret nuclear weapons program -- a charge Tehran denies.
China says it is sending a top envoy to Iran and Russia in an attempt to defuse Iran's nuclear standoff with the West. The Chinese Foreign Ministry said Assistant Foreign Minister Cui Tiankai will visit the two countries, starting Friday.