Obama warns NATO: 'Freedom isn't free'

President Obama on Wednesday expressed concern that cuts to the defense budgets of NATO members had left the alliance vulnerable, as it confronts Russia's incursion into Ukraine.

"The situation in Ukraine reminds us that our freedom isn't free, and we've got to be willing to pay for the assets, the personnel, the training that's required to make sure that we have a credible NATO force and an effective deterrent force," Obama said during a press conference following a meeting of U.S. and EU leaders.

The president said he had "some concerns about a diminished level of defense spending among some of our partners."

"If we've got collective defense, it means that everybody's got to chip in," Obama said.

Only four member countries — the U.S., U.K, Greece and Estonia — spend more than 2 percent of their gross domestic product on defense, and nearly every country in the alliance has reduced its military budget in recent years, according to an analysis by The Wall Street Journal.

By contrast, Russia has increased defense spending by nearly 80 percent over the past decade, according to a Brookings Institute study.

Obama, who will meet with NATO Secretary General Anders Fogh Rasmussen later Wednesday in Brussels, said, over the "medium and long term," the alliance would need to examine "whether everybody is chipping in."

"This can't just be a U.S. exercise or a British exercise or one country's efforts. Everybody's going to have to make sure that they are engaged and involved," Obama said.

Last week, Vice President Biden announced that the U.S. would deploy a dozen F-16 jets and 300 troops to Poland in order to boost the NATO presence there. A senior administration official also said Obama stood prepared to offer “additional support to Eastern European allies” at the meeting on Wednesday.

Earlier this year, the Pentagon proposed a $496 billion budget that was effectively flat compared to 2014 fiscal year spending levels. The budget would shrink Army forces, reduce operations for Navy cruisers, and cut the Air Force fleet. Republican lawmakers have criticized the Obama administration proposal, saying it reduces troop levels at a dangerous time for the nation's security.

Obama also seemed to rule out the possibility of expanding NATO in response to Russia's attempted annexation of Crimea, as has been suggested by some lawmakers on Capitol Hill.

"I think neither Ukraine or Georgia are currently on a path to NATO membership," Obama said, adding that there had not been any "immediate plans" to reconsider their status among current members.

Obama said NATO had been reluctant to admit Ukraine because of its ties to Russia before the current crisis, which had only complicated the situation further.

But the president declared that Russia had only strengthened the relationship between the United States and Europe with the annexation of Crimea.

"If anyone in the Russian leadership thought the world wouldn't care about their actions in Ukraine, or that they could drive a wedge between the European Union and the United States, they clearly miscalculated," Obama said.

Declaring that "Russia stands alone," Obama noted that the members of the European Union, NATO, United Nations Security Council and G-7 were all united in opposition to the incursion.

"So far, what we've seen is excellent coordination between the United States and Europe," Obama said.

"The world is safer … when Europe and America stand as one," he added.

The president and European leaders reiterated their threat that Russia would face tougher sanctions if they continued aggression in the region, and Obama called the penalties already imposed the "most significant sanctions Russia has faced since the end of the Cold War."

He also said leaders were "mindful" that additional sanctions would impact certain countries in Europe — and especially those with close energy ties to Russia — more significantly.

But European Commission President José Manuel Barroso said discussion of who was doing more to punish Russia was "really sterile and useless."

"We are united, as we have shown, taking very important decisions like the cancellation of our European Union and Russia summit or now, together, the cancellation of the G-8 summit in Sochi and indeed the organization of a G-7 meeting here in Brussels," Barroso said.