ROME (AP) - Secretary of State John Kerry says the Obama administration will provide the Syrian opposition with an additional $60 million in assistance and will for the first time provide non-lethal aid like food and medical supplies to rebels fighting to oust President Bashar Assad.

Kerry announced the new support and the policy shift on Thursday in Rome, on the sidelines of an international conference on Syria. European nations are also expected to signal their intention to provide fresh assistance to the opposition.

Kerry says the U.S. decision is designed to increase the pressure on Assad to step down and pave the way for a democratic transition. He says the aid is also intended to help the opposition govern newly liberated areas of Syria and blunt the influence of extremists.

On Wednesday in Paris, Kerry acknowledged that the Syrian opposition needs more help. Kerry said the United States still believes that a political solution is the best way to end the bloodshed, but after two years of conflict it’s clear that the process needs to be sped up.

“That may require us to change President Assad’s current calculation.  He needs to know that he can’t shoot his way out of this,” said Kerry.  “We need to convince him of that, and I think the opposition needs more help in order to be able to do that.  And we are working together to have a united position with respect to that.”

U.S. officials confirmed to ABC News that the United States is considering providing “non-lethal” help to selective rebel fighters that will include communications equipment, medical and other supplies. Under the U.S. legal definition of non-lethal assistance, any aid that is not weaponry or ammunition qualifies. That means the U.S. could also provide body armor, military training, armored vehicles and help with intelligence.

“What you’re doing is you’re giving them the capability to manage their force without giving them the weapons,” former Gen. James Cartwright told ABC News.

The United States has been providing about $50 million of non-lethal assistance to Syria’s political opposition, including providing communications equipment like radios and computers to advocates and political opposition councils.

Republican Sen. Marco Rubio said on Wednesday at the Washington Institute for Near East Policy that he thinks the United States should go further, providing ammunition for the rebel fighters. Rubio’s comments followed his recent trip to the region, where he met with the former prime minister of Syria who defected to Jordan last August.

“There are plenty of weapons in Syria. What the opposition really needs is access to ammunition,” he said. “Ammunition is something we can provide that is not weaponry per se, but is essential. That’s the stuff I’m prepared to advocate for.”

But providing weapons and ammunition to Syria’s rebel army comes with risks. Extremist elements of the opposition, including groups with ties to al Qaeda in Iraq, have emerged in the conflict. More than 50 people, many of them women and children, were killed last week in a terror attack in Damascus, Syria, carried out by a suicide bomber.

Kerry acknowledged during his Paris news conference that extremist elements within the opposition have filled what Syrians perceive as a vacuum of assistance from the U.S. and its allies.

“Some folks on the ground that we don’t support and whose interests do not align with ours are delivering some of that help,” said Kerry.

He told reporters that the United States needs to address the problem by helping Syria’s opposition do a better job to meet the needs of the Syrian people in areas they control.

“We need to help them to be able to deliver basic services…where you have a vulnerable population today that needs to be able to resist the pleas to engage in extremism,” he said.

Cartwright said that the Obama administration’s caution over the United States’ level of involvement in Syria’s drawn-out and complicated conflict isn’t surprising.

“There are people there that are clearly not from inside Syria that are participating,” Cartwright said.

“They’re either in agreement with one side or the other, or they’re there to be postured when the conflict comes to an end [so] they will be able to influence the state affairs at the end,” he added. “Not knowing that makes it very difficult to stick your nose into someone else’s fight.”

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