Samantha Power: Obama Believes Skipping Putin Meeting ‘Irresponsible’ Given Stakes

— -- Samantha Power, the U.S. ambassador to the United Nations, defended President Obama’s plans to meet with Russian President Vladimir Putin, saying that the president believes that neglecting to meet with the Russian leader while the pair are in the same city would be "irresponsible" given the high stakes.

She said the meeting between the two leaders scheduled for Monday is not an indication the U.S. strategy of isolating Putin has failed.

"Isolating him has had profound effects, as you know, on Russia's economy and his own sense of stature on the international stage, which is why I think [President Putin] is reaching out in a whole host of ways," Power said, referencing Putin's recent phone call to singer and gay rights activist Elton John.

"A hallmark of President Obama's foreign policy from the beginning has been to test engagement," Power told ABC News' Martha Raddatz on "This Week."

"And given the stakes -– the human stakes, the strategic stakes of what's going on in Ukraine and Syria -– the president believed it would be irresponsible to let this occasion in which the two leaders would be in the same city pass without trying to test to see whether progress could be made on these newly intractable crises," she said.

The president is scheduled to meet with Putin in New York City during the U.N. General Assembly. The two countries have been at odds following the Russian annexation of Crimea and support of separatists in Ukraine, and over Russia's support of Syrian President Bashar al-Assad. The U.S. has called for his removal from power.

Power accused Assad of targeting Syrian civilians and of being ineffective in the fight against ISIS. Her comments came days after the head of U.S. Central Command testified before Congress that only four or five Syrian fighters trained by American forces remain on the battlefield. Power conceded questions about the American strategy in the fight against ISIS are legitimate.

"Totally fair. Totally fair. It's obviously even more complex, I think, that we would have envisaged," Power said, adding that the Department of Defense is now reevaluating its approach.

"This is a risk management exercise. We also have to grapple with the fact that if we weren't investing in Syrian-Arab forces and in moderate Syrian opposition forces, we'd be in a world where again, ISIL [ISIS] would be able to have a protracted presence without being displaced over time. So we need to invest in this, we need to get the vetting right, and I think DoD has in mind some improvements that will enhance our prospects," she said.