Obama speech

An estimated 30,000 people streamed into the historic center of Prague on Sunday to hear Obama deliver his first major public speech in Europe since becoming president. With Prague Castle as a backdrop, Obama proposed measures to eliminate existing nuclear weapons, stop further nuclear proliferation and prevent terrorists from acquiring nuclear weapons or materials. The US leader's speech comes as the Czech Republic marks the 20th anniversary of the fall of communism.

"As the only nuclear power who have used a nuclear weapon, the United States has a moral responsibility to act," Obama said. "We cannot succeed in this endeavor alone, but we can start it."

Germany’s foreign minister Frank Walter Steinmeier has called for nuclear disarmament plans to be mobilized this year. “Nulcear weapons and their unchecked proliferation are a major threat to us all,” Steinmeier told the mass circulation German tabloid Bild am Sonntag.

Call for action on North Korea

Obama's focus on nuclear non-proliferation took on special significance as it came just hours after North Korea announced it had launched a long-range rocket into space. The rocket was launched in defiance of warnings from North Korea's Asian neighbors and Washington.

Obama condemned the North Korean move as a "provocative act." He called for a quick, joint statement condemning the launch.

"This provocation underscores the need for action," Obama said. "Violations must be punished. Words must mean something. Now is the time for a strong international response."

Pyongyang has said it was putting a communications satellite into orbit. But Japan, South Korea and Washington believe the launch was a screen to test a ballistic missile. The US and Japanese military say that the rocket failed to enter orbit.

Obama supports missile shield

Obama's speech does not mean the US has immediate plans to get rid of all its nuclear weapons. He said the United States will maintain a safe, secure and reliable nuclear capability to deter adversaries and reassure its allies.

He also indicated that the United States would "go forward" with a controversial missile defense system planned for the Czech Republic and Poland. The proposal has angered Russia, despite US assurances that the system is meant to protect Europe from an attack by Iran.

"As long as the threat from Iran persists, we will go forward with the missile system," Obama said. "If the Iranian threat is eliminated, we will have a stronger basis for security, and the driving force for missile construction in Europe will be removed." Obama did suggest that Iran could pursue its nuclear power ambitions, provided the program was subject to “rigorous inspections”.

The missile shield announcement could heighten tensions with Russia. Yet Obama said he's eager to negotiate a legally-binding arms reduction treaty with Russia and all other nuclear powers. The US will also seek to ratify a nuclear test ban treaty.

Obama discusses environment, economy

Obama's keynote speech in Prague is a highlight of his five-nation trip, which marks his first major foray onto the world stage since becoming president in January. Last week, Obama attended a summit in London on the financial crisis and marked NATO's 60th anniversary in Germany and France.

He will spend Sunday meeting with leaders of the 27-member European Union in Prague. European leaders are expected to press Obama on two global issues -- the economic crisis and climate change. He has also called for European help accepting detainees from the Guantanamo Bay prison which he intends to close early next year, and on continuing efforts to bring stability to Afghanistan.

Obama will also meet with Czech Prime Minister Mirek Topolanek, whose country holds the EU rotating presidency. The outgoing prime minister, who last month lost a vote of confidence in the Czech parliament, recently denounced Obama's massive economic stimulus plan as "the road to hell."

The next stop on Obama's first major international trip will be Turkey. Obama took the opportunity to urge EU member states to accept Turkey into the bloc, saying it would be a positive sign to the Muslim world. But French President Nicolas Sarkozy has reiterated that he is opposed to Turkey joining the EU:

“When it comes to the European Union, it’s up to member-states of the European Union to decide on membership”, Sarkozy said in an interview on French television.