* NATO allies back Obama Afghan plan
* Allies to send election reinforcements, trainers
* They stop short of long-term troop boost
STRASBOURG, April 4 (Reuters) - U.S. President Barack Obama won NATO backing on Saturday for his new approach to Afghanistan but his European allies stopped short of offering long-term troop deployments for the war effort.
Leaders of the 28-nation military alliance pledged at a summit to send 3,000 more troops on short-term assignments to boost security for Aug. 20 elections in Afghanistan, and some 2,000 more personnel to train Afghan security forces.
They also promised to send 300 paramilitary police trainers and provide $600 million to finance the Afghan army and civilian assistance, Obama said.
NATO Secretary-General Jaap de Hoop Scheffer said allies were united in support for the strategy championed by Obama, who facours a regional approach to Afghanistan with a stepped-up civilian effort and training of Afghan security forces.
He said more than 10 countries announced new contributions.
"We will be supporting the elections; we will be improving training for the Afghan soldiers," he told a news conference. "Many allies have stepped up to the plate this morning and the concrete results of this summit are very, very good indeed."
Obama, who has sought to use his popularity in Europe to wring concessions from allies, said he was pleased by the pledges and that "a substantial step forward" had been taken.
But he added: "We will need more resources and a sustained effort to achieve our ultimate goals."
He said Washington expected additional resources would be committed to support its strategy, which he said would establish a "baseline of honesty and integrity of purpose".
"It will be much more difficult for each of us in NATO to avoid or shirk the serious responsibilities that are involved in accomplishing our mission," he said.
Despite U.S. appeals, the summit saw no new long-term commitments of combat troops that would help shift the balance from what many analysts see as a increasing "Americanisation" of the international military effort in Afghanistan.
More than half the more than 70,000 foreign soldiers already in Afghanistan are Americans and this balance will tip further when thousands more soldiers Obama has ordered to have Afghanistan arrive in the country.
British Prime Minister Gordon Brown said Britain, which has the second-largest foreign force in Afghanistan, would send hundreds more troops. But, like most additional forces from other European countries, these would be only temporary reinforcements for the election period.
Even so, Obama's conciliatory tone has gone down better than that of his predecessor George W. Bush, who was deeply unpopular in Europe and whose administration sometimes bullied allies publicly to bolster their contributions in Afghanistan.
"I think there's an Obama effect. The discipline in focusing on clear objectives, a clear strategy and then calling for resources to support, it has undoubtedly yielded dividends," British Foreign Secretary David Miliband told Reuters.
Obama's Afghan plan aims to get a grip on rising violence by Taliban militants driven from power in 2001 but never completely defeated, broadening the focus to Pakistan and putting the highest priority on the defeat of al Qaeda militants.
European leaders have been reluctant to send more of their own soldiers to a war that is unpopular with voters, preferring to focus their energies on reconstruction and development. (Editing by Timothy Heritage)
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