WASHINGTON — President Barack Obama will consult about the Paris terrorist attacks with world leaders in Turkey this weekend as the annual gathering of presidents and prime ministers from the world's largest economies there is poised to become an urgent summit meeting on confronting extremism.
The president boarded Air Force One on Saturday afternoon for a 10-day trip to Turkey, the Philippines and Malaysia, a day after a series of simultaneous attacks in Paris prompted President François Hollande of France to tighten the nation's border controls and mobilize the military. Before leaving, Obama convened a meeting of his National Security Council to review the latest intelligence on the attacks, officials said.
On Friday evening, Obama called the situation in Paris an "attack on all of humanity" and pledged to do whatever it takes to join the French people in bringing the terrorists to justice. The president is expected to arrive early Sunday morning in Antalya, Turkey, on the Mediterranean coast, for the Group of 20 summit meeting.
The official economic agenda in Turkey and Asia was already likely to be overshadowed by a series of intense meetings between Obama and his counterparts about the Syrian civil war, the refugee crisis in Europe, disputes with President Vladimir Putin of Russia and ongoing tensions in the South China Sea.
But the Paris attacks are certain to push even those topics to the side, at least temporarily, as world leaders confront the scale of the terrorist attacks in the French capital. The leaders will grapple with the rising threat of the Islamic State, which Hollande has blamed for the Paris attacks. U.S. authorities on Saturday did not dispute Hollande's assessment or the Islamic State's own claim of responsibility.
There was no official word early Saturday about possible changes to the schedule of events in Turkey, which were to feature an opening ceremony and sessions on development, climate change, the global economy and growth. A dinner to discuss terrorism and refugees was already planned for Sunday night.
Obama had been scheduled to meet one-on-one with Hollande, but the French president canceled his visit to Turkey soon after the scale of the attacks became clear.
Six years after Obama attended his first G-20 meeting at the height of the global economic crisis in 2009, the U.S. economy has rebounded and the president was looking forward to attending this year's gathering as the leader of one of the world's strongest economies.
To the Philippines and Malaysia, Obama will bring the just-negotiated Trans-Pacific Partnership trade deal, and a pledge to win its passage by Congress back home. The president planned to preview his hopes for a new global climate pact that is scheduled to be concluded during a summit meeting in Paris that begins late this month. It was unclear Saturday what impact the terrorist attacks in that city might have on the climate meeting.
Obama had also planned to use the summit meetings to make diplomatic progress after recent military advances in Iraq against the Islamic State, also known as ISIS and Daesh, which has seized vast territory in both Iraq and Syria. Secretary of State John Kerry has been trying to forge a diplomatic path that could lead to the eventual departure from Syria of President Bashar Assad and an end to four years of conflict in the country.
Kerry met in Vienna on Saturday with diplomats from Europe and the Middle East, seeking progress on establishing a cease-fire and resolving differences about the future of Assad's government.
Obama's conversations with world leaders are scheduled to take place not far from Turkey's border with Syria, a transit point for refugees. Before the Paris attacks, aides to Obama had expressed hope for what they called "incremental" movement during the president's discussions, but they cautioned that negotiations would need to continue beyond the president's trip to the region.
"These issues are hugely complex and fraught," said Susan E. Rice, the president's national security adviser. "If they weren't, they would have been resolved a long time ago."
"I don't think anybody expects a single outcome that all of a sudden readily resolves all these difficult issues," she added.
Not on the official schedule is a meeting between Obama and Putin, who is expected at the summit meeting in Antalya. But even before the Paris attacks, White House officials said they had anticipated that the two leaders would have "ample opportunity" to talk privately. The last meeting between the two men, at the U.N. General Assembly in September, was described as confrontational, even before Putin expanded his country's own military involvement in Syria.
It was unclear Saturday whether the Paris attacks might alter the dynamic between Obama and Putin. The bloodshed in France comes after a terrorist attack in Lebanon and the crash in Egypt of a Russian airliner, which is thought to have been brought down by a terrorist bomb.
Speaking before the Paris attacks, Heather Conley, a former deputy assistant secretary of state under President George W. Bush, said "Mr. Putin will be far from isolated" at the summit meeting. Conley, now at the Center for Strategic and International Studies, added that "Russia now plays an increasing role in how to resolve the political transition in Syria."
But Rice rejected that assessment of Putin. "The Russians certainly have their ideas; we have ours; other players have theirs," she said, adding that she did not see "any indication that President Putin's isolation is diminished."
Later in his trip, Obama is expected to highlight the Pacific trade agreement to underscore what White House officials call his long-term commitment to a larger American presence in Asia.
Obama is not expected to meet with President Xi Jinping of China, although the two leaders will both attend the Asia-Pacific Economic Cooperation summit meeting in the Philippines. But officials said Obama would make concerns about freedom of navigation through the South China Sea a "central issue of discussion" during his visits.
"The United States takes no position on competing sovereignty claims" in the South China Sea, Josh Earnest, the White House press secretary, said in a news briefing before the Paris attacks. "But what we do take a strong position on is protecting the rights, freedoms and lawful uses of the sea and airspace that's guaranteed to all countries."
Obama is certain to hear much on that subject from other Asian leaders, many of whom want help from the United States in standing against China's claims on the disputed waters off its coast. In late October, the administration sent a Navy destroyer through the disputed waters in what officials called a "freedom of navigation" exercise designed to send a signal to the Chinese.