National flags were to be raised and anthems sung at the first Brussels meeting of the now-26-nation alliance joined by the foreign ministers of Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia.

US Secretary of State Colin Powell was to be among the dignitaries on hand to welcome the new members, which joined NATO on Monday by depositing their accession treaties in Washington to take the alliance up to Russia's borders.

Moscow has made no secret of its intense irritation at NATO's biggest expansion ever, especially at the inclusion of the Baltic states -- Estonia, Latvia and Lithuania -- which used to be part of the Soviet Union.

Russian Foreign Minister Sergei Lavrov was to get a chance to vent his country's ire at a regular session of the NATO-Russia Council on Friday following the morning ceremony for the new members.

The arrival of the seven new member states comes at a critical juncture for NATO, which was created in 1949 to defend western Europe from the Soviet Union but is now remoulding itself to confront new challenges.

In the wake of the March 11 attacks in Madrid, a NATO official said Friday's talks would look "at ways in which we can energize further our counter-terrorism efforts", specifically through sharing intelligence.

Already active in the Balkans and in Afghanistan, the alliance is also in talks about taking a formal peacekeeping role under the US-led occupation of Iraq. Individually, most of its members already have troops there.

The foreign ministers were also set to debate plans for NATO peacekeepers to fan out from the Afghan capital Kabul to the rest of the turbulent country.

At a donors' conference in Berlin Thursday, NATO said it would establish another five provincial reconstruction teams (PRTs) in Afghanistan and assist security during elections planned for September.

PRTs are mixed groups of lightly-armed military and development personnel which have been helping deliver aid in remote provinces not covered by the NATO-led security force (ISAF), which is limited mainly to Kabul.

Recent deadly unrest in the Serbian province of Kosovo, where NATO troops are also involved, was also on the agenda for Friday's talks.

And Powell was expected to bring up a US plan to extend to Middle Eastern countries the kind of cooperation established between NATO and former Soviet bloc nations under the "Partnership for Peace" programme.

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