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By Matt Spetalnick and Susan Cornwell
BUCHAREST, April 2 (Reuters) - U.S. President George W. Bush sought to salvage his legacy on the world stage on Wednesday by defending the wars in Iraq and Afghanistan and appealing to Russia to drop opposition to a U.S. missile defence shield.
Laying out his agenda for his farewell NATO summit, Bush also pressed the defence alliance to put Ukraine and Georgia on the path to membership despite French and German qualms that it could further strain Moscow's relations with the West.
Bush's keynote speech at a pre-summit conference in Bucharest read like a laundry list of his foreign policy woes as he struggles to stay relevant abroad in the twilight of his second and final term.
But with Bush even more unpopular overseas than at home, he could have a hard time swaying world leaders as they look to whomever will succeed him as president in January 2009.
Bush is aware that NATO allies have grown weary of the war in Afghanistan against a resurgent Taliban and its al Qaeda allies but called on partners to send more troops there, saying they could not afford to lose the battle.
"Our alliance must maintain its resolve and finish the fight," Bush said. "We must ask other NATO nations to step forward with additional forces as well."
The issue of troop levels in Afghanistan, where some NATO allies have shied away from areas of heavy combat, has caused trans-Atlantic finger-pointing and was expected to remain a source of tension at the NATO summit starting on Wednesday.
European critics accuse Bush of being distracted by the Iraq war, which has helped cement a go-it-alone image in world affairs. They say he has not paid enough attention to what they see as a more important fight in Afghanistan.
With Iraq expected to define Bush's presidential legacy, he kept up his defence of the five-year-old war, which has damaged credibility with friends and foes alike.
Bush said a U.S. troop buildup in Iraq had yielded significant security progress. "There's tough fighting ahead, but the gains from the 'surge' we have seen are real," he said.
But the latest increase in fighting has increased doubts of major drawdowns of U.S. forces before Bush leaves office.
APPEAL TO PUTIN
With U.S.-Russia relations deemed to have sunk to a post-Cold War low, Bush also appealed to Russian President Vladimir Putin to embrace the U.S. plan for a missile defence system partly based in Poland and the Czech Republic.
Putin, who will be a guest at the Bucharest summit, has fiercely criticised Washington's plan.
Bush again said the missile shield was not aimed at Moscow but was meant to deter missile threats from countries such as Iran that Washington considers dangerous.
"The Cold War is over. Russia is not our enemy," he said.
After the summit, Bush will fly to Russia for final talks with Putin, who steps down in May.
At the talks in a villa in the Black Sea resort of Sochi, they hope to use their personal chemistry to repair relations strained over missile defence, Kosovo's independence and NATO expansion.
Diplomats have sketched a possible trade-off, in which Moscow would accept U.S. plans to deploy its missile shield and Washington would accept a delay in the NATO bids for Georgia and Ukraine, which Russia sees as part of the former Soviet orbit.
But Bush has denied any such deal is on the table.
U.S. officials have said the Sochi talks could yield a "strategic framework" of U.S.-Russia relations. But the meeting could also help Bush gauge how much power Putin will wield behind the scenes after Dmitry Medvedev, his protege, takes over as president. Putin is widely expected to become prime minister.
Critics say Bush was naive to believe Putin was committed to lasting democratic reform. Aides say he is now more realistic about Putin, who has become more assertive of Russia's place in world affairs and makes strident criticisms of U.S. policies.