U.S. President Barack Obama says the existence of nuclear weapons is the "most dangerous legacy of the Cold War."
Addressing tens of thousands of people in square at Prague Castle in the Czech Republic Sunday, Mr. Obama outlined his strategy for eventually eliminating the world's existing nuclear arsenals.
The U. S. president called for reaching a new strategic arms reduction treaty with Russia by the end of the year and announced plans to push the U.S. Senate to ratify the Comprehensive Test Ban Treaty.
He called Korea's missile launch earlier Sunday a violation of the rules. He said the time has come for a strong international response.
Mr. Obama also repeated proposals for contacts with Iran on halting its nuclear program, but said the United States will go forward with a missile shield in Europe as long as Iran remains a threat.
He also called for a new international treaty that verifiably ends the production of fissile material for nuclear weapons and that will include China, India and Pakistan.
Czech President Vaclav Klaus greeted Mr. Obama in Prague, where the U.S. president meets with European Union leaders.
The Czech Republic currently holds the rotating European Union presidency, and opinion polls suggest many Czechs fear the planned missile defense radar installation could create tensions with Russia and more insecurity in Europe.
Despite a ban on protests, demonstrators have planned a number of rallies for Sunday. About 300 opponents of a planned U.S. missile defense radar base in the Czech Republic protested Saturday.