NATO is standing firm behind the United States in its determination to crush terrorism, the NATO secretary general said.
Lord Robertson says the Article 5 declaration that an attack on one of its members is an attack on all has real meaning.
He has dismissed suggestions the coalition against terrorism that US President Mr George W. Bush and British Prime Minister Mr Tony Blair are trying to put together is looking wobbly.
Lord Robertson said: "That is not my impression. I don't think that's the case at all.
"I watched President Chirac yesterday on television in the US, there wasn't a flicker of doubt in his mind that they would stand by the US.
"Chancellor Schroeder made it absolutely clear yesterday that Germany accepts not just its obligations under Article 5, but its obligations to stand by a country that has been attacked in a way that Germany and other countries could be as well.
"So I can tell you that the alliance stands firm and the declaration made last Wednesday was not only historic, it was actually practical in its implications too," he said.
But Lord Robertson warned: "We are up against people who are using techniques that would have been unimaginable only a few weeks ago, and I think therefore we have got to think differently".
PA