BRUSSELS, April 2: Nato members celebrated their alliance's biggest ever expansion on Friday at a colourful and emotional ceremony marking the entry of seven ex-Soviet bloc nations into the once fiercely anti-communist military organization.

As flags from new members - Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia - were raised at the Nato headquarters in Brussels, foreign ministers from old and new alliance nations hailed the final, formal end of Europe's Cold War east-west divide.

"Today is the clearest demonstration that in Europe, geography no longer equals destiny," said Nato Secretary-General Jaap de Hoop Scheffer.

New Nato members said joining the alliance was the completion of a long-held goal.

"This morning a dream has been fulfilled," said Latvian Foreign Minister Rihards Piks, adding: "This is truly a moment to be enjoyed like no other".

The alliance's expansion to 26 members - combined with the European Union's enlargement on May 1 - represents a dramatic redrawing of Europe's strategic map.

Nato, set up in 1949 by the United States, Canada and 10 western European states seeking to bolster western defences against the defunct Soviet Union, is now turning its attention to new challenges.

"The fight against terrorism is high on our agenda," Mr de Hoop Scheffer said.

Far from its initial operational zone, Nato is seeking to keep peace in the Balkans and in Afghanistan.

The shift in priorities comes after last year's deep divisions in Nato over the US-led war in Iraq with key alliance members Germany and France opposing the war.

These differences could re-emerge as the US steps up its campaign for a stronger Nato role in Iraq.

New Nato members make no secret of their readiness to extend the alliance's presence in Iraq. Germany and France are still cautious, however.

Seeking to ease Russian concerns over the expansion of Nato, all 26 Nato foreign ministers met their Russian counterpart Sergei Lavrov on Friday. "We need a constructive partnership with Russia," said Mr de Hoop Scheffer. "An enlarged Nato can have the same good, constructive relationship with Russia as before," he insisted.