WASHINGTON (CBSNewYork/AP) — President Barack Obama said in a news conference on Thursday that the United States will keep going after the Islamic State of Iraq and Syria “aggressively in every front” of the military campaign.

The news conference came after Obama summoned top military and national security officials to the Pentagon to assess what’s working and what’s not in the fight against ISIS.

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Obama said that ISIS has been losing ground in both Iraq and Syria.

“Even ISIL’s leaders know that they’re going to keep losing, and their message to followers that they’re increasingly acknowledging that they may lose Mosul and Raqqa and ISIL is right, they will lose them,” the president said, using a different acronym for ISIS. “And we’ll keep hitting them and pushing them back and driving them out until they do. In other words, ISIL turns out not to be invincible, they are, in fact, inevitably going to be defeated.”

Despite ISIS losing ground, Obama warned the terror group will still be a threat to the United States and the West.

“It should be clear by now, and no one knows this better than our military leaders, that even as we need to crush ISIL on the battlefield, their military defeat will not be enough, so long as their twisted ideology persists and drives people to violence, then groups like ISIL will keep emerging and the international community will continue to be at risk in getting sucked into a global whack-a-mole where we’re always reacting to the latest threat or the lone actor,” the president said.

Obama also criticized Russia for its continuing support of Syrian government attacks against opposition forces and its sieges of populated areas like Aleppo.

“Russia’s direct involvement raises very serious questions about pulling the situation back from the brink,” Obama said.

Obama told reporters at the Pentagon that the U.S. will continue to try to cooperate with Russia to reduce the violence and focus the fight on ISIS and other extremists.

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He accused Russia of failing to take the necessary steps to do that, though, adding that deteriorating conditions make it imperative for Russia to show it is serious.

Obama and Vice President Joe Biden made the short trip across the Potomac River to sit down with Defense Secretary Ash Carter, CIA Director John Brennan and other Cabinet secretaries.

The session comes as the U.S. is bombing targets in and around the Libyan city of Sirte, a notable expansion of the U.S.-led coalition’s military mission against ISIS. At the urging of the Pentagon, Obama authorized the strikes that started this week and include precision strikes against IS tanks, rocket launchers and fighting positions.

Italy, just across the Mediterranean Sea from Libya, has said it’s prepared to allow the U.S. to use its bases or airspace to launch strikes against ISIS in Libya. The extremist group’s spread to Libya and elsewhere in North Africa has deeply alarmed European countries already worried about the specter of terrorism in European cities.

Obama typically convenes the National Security Council at the White House, but over the past year he has occasionally held them at other agencies like the State Department and the CIA. The goal of the road show at the Pentagon is to illustrate the multifaceted U.S. approach to defeating IS.

Mired in chaos following the ouster of strongman Moammar Gadhafi in 2011, Libya became a target for ISIS extremists hoping to build a safe haven outside its initial territory in Iraq and Syria. Though the number of ISIS fighters in Libya has dwindled, the U.S. is hoping to help Libya’s fledgling U.N.-backed unity government finish the job.

Obama also plans to use the meeting at the Pentagon to praise recent gains by the U.S. and its partners against ISIS in Syria and Iraq. With significant U.S. help, Iraq’s government is preparing a major offensive to reclaim the key northern city of Mosul, controlled by ISIS since June 2014.

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