Obama Urges Iran to Affirm Peaceful Nuclear Energy

US President Barack Obama, second right, walks with Czech President Vaclav Klaus towards the Castle...

US President Barack Obama, second right, walks with Czech President Vaclav Klaus towards the Castle in Prague, Czech Republic, on Sunday, April, 5, 2009. Seen in background are Obama's wife Michelle, left, and Klaus' wife Livia following their husbands. Obama had a meeting with his Czech counterpart Vaclav Klaus and Czech Prime Minister Mirek Topolanek at the Prague Castle before delivering a public speech on the castle's square. Obama later on Sunday attends a summit with EU leaders. (AP Photo/Anja Niedringhaus)

(AP)

President Barack Obama said the U.S. will proceed with development of a missile defense system in Europe as long as there is an Iranian threat of nuclear weapons.

He said that if that threat is removed, "The driving force for missile defense in Europe will be removed."

In his speech before cheering crowds in historic Prague, Obama said the U.S. will present Iran with "a clear choice" to cease its nuclear and ballistic missile activity or face increased isolation and a nuclear arms race in the Middle East.

"Let me be clear: Iran's nuclear and ballistic missile activity poses a real threat, not just to the United States, but to Iran's neighbors and our allies," the president said. "As long as the threat from Iran persists, we intend to go forward with a missile defense system that is cost-effective and proven."

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