NATO:Nato pledged yesterday to stay the course to restore peace and stability in Afghanistan at a summit where nations offered guarded concessions to improve the mobility of allied forces battling Taliban insurgents.
Alliance leaders also reversed policy on Serbia and Bosnia by offering them a first step towards Nato membership and said other Balkan nations could expect entry invitations in 2008.
"We are committed to an enduring role to support the Afghan authorities, in co-operation with other international actors," the 26 leaders of the military alliance said in a joint statement after talks in the Latvian capital Riga.
"It is winnable, it is being won, but not yet won," said Nato secretary general Jaap de Hoop Scheffer of the most dangerous ground combat in the alliance's 57-year history.
British prime minister Tony Blair, whose troops are bearing much of the brunt of daily violence in southern Afghanistan, said all Nato leaders agreed that Nato's credibility "was on the line" over Afghanistan.
US president George W Bush said success in Afghanistan could come only if allies accepted "difficult assignments" after alliance commanders complained the mission has been hobbled by limits many nations set on how their forces are deployed.
Mr Blair's official spokesman said Bulgaria, Spain and Nato aspirant Macedonia had offered more forces and Mr de Hoop Scheffer said countries had pledged to lift or ease limits that would make 26,000 of the 32,000-strong Nato peace force more mobile.
But many major nations, including France, Germany and Italy, said their contingents could be moved to Afghanistan's more perilous regions only in emergencies. German chancellor Angela Merkel resisted pressure to deploy outside its base in the relatively calm north.
French officials said France could "on a case-by-case basis" send troops outside their zone around the capital Kabul, while Spain promised the use of its helicopters - but not for combat.
Nato leaders also backed a French idea for an Afghan "contact group". Mr de Hoop Scheffer will explore the idea of a steering group like the committee of nations that has co-ordinated diplomacy in the Balkans for more than a decade.
Some US officials had voiced private misgivings about the idea because it might give Afghanistan's neighbour Iran, with which Washington has no ties, a seat at the table.
As part of the alliance's efforts to revamp itself from Cold War monolith to a more fleet-of-foot global security provider, Nato leaders declared a long-awaited 25,000-strong rapid reaction force fully operational.
Russian president Vladimir Putin caused a diplomatic frenzy in Latvia on Tuesday by offering to drop in on the former Soviet republic after the summit to congratulate French president Jacques Chirac, a political ally, on his birthday. The visit was cancelled due to scheduling difficulties.