BUCHAREST, Romania (AP) --
The summit has been troubled by divisions, most notably opposition from France and Germany to giving Ukraine and Georgia a plan for eventually joining NATO. Bush indicated that was an open question because any NATO member can block it.
"We'll see," he said, saying one country was still an issue.
Bush has pushed NATO countries to commit more troops to the 47,000-strong NATO force in Afghanistan. At least 10 countries, including France, Germany, Norway and Poland, have announced they would do so. Bush would like to see more.
"I feel good about what I'm hearing from my fellow leaders about their desire to support Afghanistan," the president said. "I think if tomorrow we get clarification on troop support ... the people of Afghanistan are going to be more than grateful." He did not mention any specific numbers of additional troops.
The U.S. is the biggest contributor of troops in Afghanistan, numbering 17,000 in the NATO-led force and 14,000 in a U.S.-led contingent in eastern Afghanistan that trains Afghan forces and hunts al-Qaida. The U.S. presence is set to expand by 3,500 Marines, most of them dedicated to the NATO mission.
Bush has spent months trying to persuade Russia that it has nothing to fear from a missile defense shield in Europe, based in Poland and the Czech Republic.
"It looks like to me that the agreement is coming together" within NATO at least to support a defensive system, Bush said. The president plans to meet with Russian President Vladimir Putin on Sunday in the resort city of Sochi. The White House has held out hopes of an agreement easing Russia's opposition to a missile shield.
Putin should "welcome NATO because it is a group of nations dedicated to peace," Bush said.
De Hoop Scheffer told Bush, "I can share and echo your optimism." He said NATO would "take a clear position on missile defense."
The NATO chief also said the alliance would publish a "vision statement" about expanding its traditional role to "the front lines in the fight against terrorism."
De Hoop Scheffer was optimistic about adding new members to NATO. Croatia, Albania and Macedonia are hoping to get invitations this week, although Greece may block Macedonia.
Taking note of the dispute over Ukraine's hopes for eventual membership, de Hoop Scheffer said, "I think this can never be a question of whether ... I think the door should be open." He did not say whether Ukraine's chance to start the process, along with Georgia, would come now or have to wait.
Earlier Wednesday, after meeting with Romania President Traian Basescu, Bush urged NATO allies to recognize the seriousness of the anti-Taliban mission in Afghanistan and step up with more troops for the fight.
"We expect our NATO allies to shoulder the burden necessary to succeed," Bush said, appearing alongside Basescu at a new conference on a wind-whipped Black Sea beach.
He stepped around the dispute between member nations that have combat troops in Afghanistan's most dangerous areas and those that are limiting their forces to the more stable north and west.
"Nations need to take this mission seriously," the president said. "It's worth it for our own security and it's worth it for the cause of peace."
Basescu, standing with Bush after their talks at a gated seaside complex of villas amid evergreens, endorsed Bush's call. Romania has indicated it plans to increase its presence in Afghanistan; the specifics have yet to be announced.
"Any lack of success of NATO in Afghanistan will diminish dramatically the credibility of our organization," he said through a translator.
A standoff is expected at the summit over putting Ukraine and Georgia, two former Soviet republics, on the path toward NATO membership. Russia, who is not in NATO, vehemently objects.
Ahead of the Bush-Putin meeting, White House officials have raised expectations the talks could produce a breakthrough on missile defense as part of a broader "strategic framework" to define the relationship in several areas after Bush and Putin leave office.
"I call it an opportunity to sit down and have a good, frank discussion again," Bush said. He said he will make clear to Putin that "the Cold War is over and Russia is not our enemy."
Before went to Romania's coast, he spoke to 500 political and business leaders in Bucharest about Afghanistan, missile defense, NATO and Iraq.
"If we do not defeat the terrorists in Afghanistan, we will face them on our own soil," Bush said. "Innocent civilians in Europe and North America will pay the price."
He said the missile defense system was critical to defending against a "real and, in my opinion, urgent" threat posed by nations such as Iran.
Bush sought to counter misgivings from France and Germany that opening the NATO membership process to Ukraine and Georgia could sour relations with Moscow, an important energy supplier. "NATO membership must remain open to all of Europe's democracies that seek it, and are ready to share in the responsibilities of NATO membership," he said.
With nine ex-Soviet bloc countries already in the alliance, Moscow is sensitive to any further loss of influence in the former Soviet sphere.
"What's happening will not (go) unanswered, I assure you," Russian Foreign Minister Sergey Lavrov said Wednesday before the State Duma in Moscow.
On Iraq, Bush said the U.S. "will not abandon our friends in the fight against terror and extremism."
Gen. David Petraeus, the top U.S. commander in Iraq, and Ryan Crocker, the U.S. ambassador, are report to Congress on the status of the war April 8-9.
He is expected to endorse their recommendation that any new decreases should wait until at least fall, and only after officials ascertain that further drawdowns would not compromise security gains.