US president Barack Obama was mobbed by cheering crowds after arriving in France today for a Nato summit, where he hopes to secure backing for his new strategy over Afghanistan.
Mr Obama said he wanted to see a world without nuclear weapons, but warned Europe that it had to face up to the threat still posed by al-Qaeda.
Mr Obama announced last week he was going to dispatch more troops to Afghanistan as part of a new strategy to battle a growing insurgency that is spreading to neighbouring Pakistan.
European leaders are reluctant to send more of their own soldiers to the war, preferring to focus their energies on civilian reconstruction and development projects.
Speaking in a US-style town hall meeting before thousands of European young people, Mr Obama said he supported these efforts but that the military operation needed more support.
"Europe should not simply expect the United States to shoulder that burden alone. This is a joint problem that requires a joint effort," he said.
Mr Obama said al Qaeda posed more of a threat to Europe than to the United States. "...It is probably more likely that al Qaeda would be able to launch a serious terrorist attack on Europe than on the United States because of proximity," he said.
French President Nicolas Sarkozy enthusiastically endorsed the strategy following talks with Mr Obama, but made clear that France itself would not be adding to its 2,780 troop contingent.
"There will be no French military reinforcements ... We are ready to do more in the field of policing, of gendarmes, in the field of economic aid, to train Afghans," he said, standing alongside Mr Obama.
Although his message was sometimes tough, Mr Obama himself presented a new image of the United States to Europe following the uncompromising presidency of his predecessor, George W. Bush.
"The United States cannot confront challenges alone but Europe cannot confront them without America," he said.
He was greeted by cheering crowds when he arrived in Strasbourg, fresh from his economic diplomacy at the G20 summit in Britain, and was equally feted when he travelled the short distance across the border to Germany.
Mr Obama warned that although the Soviet Union, had gone, the threat of nuclear catastrophe remained.
"Even with the Cold War over, the spread of nuclear weapons or the theft of nuclear material could lead to the extermination of any city on the planet," he told the town hall meeting.
"This weekend in Prague, I will lay out an agenda to seek the goal of a world without nuclear weapons," he said, referring to a EU-US summit in the Czech Republic on Sunday.
The NATO summit starts with a dinner in Germany where talks will initially focus on often difficult relations with Russia.
"It is important for NATO allies to engage Russia, and to recognise that they have legitimate interests, in some case we have common interests, but we also have some core disagreements," Mr Obama said after talks with Sarkozy.
Reuters