NEW YORK — Fresh from successes on Iran and with the pope, President Barack Obama still carried heavy burdens into critical meetings this week at the U.N. General Assembly.
They include the threat from Islamic State militants in Iraq and Syria, as well as the Syrian civil war and the ensuing refugee crisis, and Russia's moves in Ukraine and in Syria.
Obama arrived late Sunday morning for three days in New York, and perhaps the most anticipated moment was to come Monday evening — a meeting with Russian President Vladimir Putin on the sidelines of the annual gathering of world leaders.
It will be their first face-to-face meeting in nearly a year. Both leaders also were to address the opening of the assembly's annual ministerial meeting on Monday.
The U.S. and Russia have quibbled over who requested the meeting and what the focus will be. Putin wants to talk about Syria; Obama wants to concentrate on Ukraine.
Despite administration efforts to turn Putin into an international pariah after Russia annexed the Crimean Peninsula from Ukraine in March 2014, Obama believes not engaging with the Russian leader "would be wrong" given the pressing issues in Ukraine and Syria, Obama deputy national security adviser Ben Rhodes said.
Putin has begun a military buildup in ally Syria for reasons that U.S. officials have said remain unclear.
In preparation for Obama's meeting with Putin, Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov on Sunday discussed Russia's military involvement in Syria, including the possibility of a political transition in the war-torn country, according to a senior U.S. official. Kerry and Lavrov also talked about Ukraine.
The White House also announced that Obama would meet with Cuban President Raul Castro on Tuesday. It will be their second meeting since the U.S. and Cuba restored diplomatic ties late last year, and will follow Pope Francis' visit to both countries.
Obama is fresh off a successful White House meeting with Francis. In remarks to throngs at an outdoor welcome ceremony last Wednesday, the pontiff voiced support for Obama policies on climate change, immigration and economic inequality — some of which have been blocked by Republican lawmakers.
Shortly before Francis arrived in Washington, Obama achieved a major victory when opponents of the Iran nuclear deal failed to muster enough support for a congressional resolution disapproving of the agreement. That spared Obama from having to make good on his threatened veto.
The U.S., Germany, Britain, China, Russia and France have agreed to lift economic sanctions on Iran in exchange for restrictions on its nuclear program. Republican lawmakers opposed the deal on grounds that it will not keep Iran from ever acquiring a nuclear weapon.
Despite progress on the Iran nuclear front, Obama remains challenged elsewhere in the Middle East.
A campaign against IS militants who have claimed broad sections of Iraq and Syria remains far from achieving Obama's goal to "degrade and ultimately destroy" the group, despite more than a year of military airstrikes against IS targets by a U.S.-led coalition of more than 60 countries.
A separate U.S. effort to train thousands of moderate Syrian rebels to fight IS has turned out to be a costly failure, with fewer rebels than originally anticipated involved.
Obama's first stop in New York was at a U.N. summit on steps to eradicate extreme poverty around the world. He committed the U.S. to the 15-year plan endorsed by the U.N.'s 193 members. Later Sunday, the president was headlining a Democratic Party LGBT fundraiser.
Besides the address to the General Assembly and meeting with Putin, Obama also was to meet Monday with Indian Prime Minister Narendra Modi and lead a summit on international peacekeeping.
Obama likely will use the speech to argue the merits of diplomacy and engagement. Rhodes said diplomacy was most notably instrumental in the Iran deal and U.S. overtures to Cuba. Rhodes said diplomacy is also needed, sometimes "backed by teeth," to reach a political resolution in Syria and Ukraine.
"The case the president will be making to the world is we need to remain invested in an international order that can solve problems and hold people accountable when they break the rules," he said.
Obama planned to lead a summit on countering the Islamic State and violent extremism, and meet with President Nursultan Nazarbayev of Kazakhstan on Tuesday before returning to Washington.
AP Diplomatic Writer Matthew Lee contributed to this report.
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