Bush, who refused to rule out the use of force against Tehran, said he supported diplomatic overtures led by Britain, France and Germany but warned that "results of this approach now depend largely on Iran." "The free world shares a common goal. For the sake of peace, the Iranian regime must end its support for terrorism and must not develop nuclear weapons," he said at the Concert Noble, an opulent gala venue.
In remarks expected to delight many European leaders, Bush recommitted himself to ending the Israeli-Palestinian conflict and to "raise the flag of a free Palestine."
"Our greatest opportunity and immediate goal is peace in the Middle East. After many false starts and dashed hopes and stolen lives, a settlement of the conflict between Israelis and Palestinians is now within reach," he said.
Just days before he was to meet with Russian President Vladimir Putin, Bush scolded Moscow over a series of recent steps widely seen as autocratic and explicitly tied democratic reforms to Russia's relations with the West.
"Russia's future lies within the family of Europe and the trans-Atlantic community," he said. "Yet for Russia to make progress as a European nation, the Russian government must renew a commitment to democracy and the rule of law.
"And the United States and all European countries should place democratic reform at the heart of their dialogue with Russia," said Bush, who was to hold talks with Putin in the Sloval capital Bratislava on Thursday.
Alarm bells rang in the United States after Putin's moves against the oil giant Yukos, a clampdown on the media, new Kremlin authority to appoint regional officials and alleged interference in Ukraine's presidential election.
"We recognise that reform will not happen overnight. We must always remind Russia, however, that our alliance stands for a free press, a vital opposition, the sharing of power, and the rule of law," said the US president.
Bush also had some of his warmest words yet for the European Union as he prepared to host a peacemaking dinner with French President Jacques Chirac, who has said the EU may serve as a global counterweight to the United States.
"America supports a strong Europe, because we need a strong partner in the hard work of advancing freedom and peace in the world," said Bush, who sought to downplay the deep transatlantic divisions over the war in Iraq.
"Our strong friendship is essential to peace and prosperity across the globe, and no temporary debate, no passing disagreement of governments, no power on Earth will ever divide us," he said.
"Now is the time for established democracies to give tangible political, economic and security assistance to the world's newest democracy," he said.
Belgian Prime Minister Guy Verhofstadt, whose country was among the critics of the US war against Iraq, introduced Bush and called for an end to the frequently nasty debate over the March 2003 invasion to topple Saddam Hussein.
"It makes little sense to continue arguing about who was right and who was wrong," said Verhofstadt, who was all smiles and warm handshakes with Bush when they met earlier in the day.
But even before Bush's remarks, EU foreign policy chief Javier Solana said in an interview that "Iraq is not over" and that it was "a little too early to say" whether January 30 elections there would yield a regime friendly to the West.
Bush was to travel to Germany on Wednesday for talks with German Chancellor Gerhard Schroeder before heading to Bratislava to see Putin for their first meeting since a falling out over contested presidential elections in Ukraine.