President Barack Obama said Friday that the United States and its allies are preparing to “take the fight,” to the Islamic State of Iraq and Greater Syria (ISIS), saying the world can’t merely “contain” the extremist militant group and must work to dismantle it.

Speaking to reporters after two days of meetings of the North Atlantic Treaty Alliance in Wales, Obama said he was encouraged by the unanimous recognition of the threat to NATO member states from ISIS, and that the U.S. and international partners are preparing to act “with urgency.”

“We are going to achieve our goal,” Obama said. “We are going to degrade and ultimately defeat [ISIS].”

Obama’s language was notably stronger than his comments on the extremist group Wednesday in Estonia, when he suggested that the U.S. goal would be to contain the threat. Obama said Friday that “you can’t contain” ISIS, which has captured large swaths of Iraq and Syria and oppressed masses of civilians. “The goal has to be to dismantle them,” the President said.

Obama highlighted the importance of building an international coalition to take on the group, saying his “expectation” is that efforts to secure the backing of Arab states in the region will prove fruitful.

“There’s great conviction that we have to act, as part of the international community, to degrade and ultimately destroy [ISIS],” Obama said.

The President defended his administration’s approach to tackling the group, saying the first phase of his strategy, to encourage the Iraqi people to form a more inclusive government, has paid off, while the second, to use targeted airstrikes and humanitarian airdrops to keep the group from expanding, is ongoing.

“The third phase will allow us to take the fight to [ISIS], broaden the effort,” Obama said.

Obama also addressed the cease-fire reached between Ukraine and pro-Russian separatists Friday, saying “it has to be tested.”

“Obviously we are hopeful but, based on past experience, also skeptical that in fact the separatists will follow through and the Russians will stop violating Ukraine’s sovereignty and territorial integrity,” Obama said.

The United States and the European Union are considering additional sanctions to be imposed on Russia as a response to confirmation that Russian forces have been directly involved in combat in eastern Ukraine, and Obama indicated the ceasefire is unlikely to preempt those sanctions. Obama said imposing the sanctions and lifting them if Russia and the separatists live up to the agreement would be a “more likely way for us to ensure that there’s follow-through.”

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