The United States promised Thursday to send food and medical supplies -- but not weapons -- to rebels in the first such move since the conflict began two years ago.

At the same time, European nations began to explore how to strengthen rebel fighters short of arming them after a European Council decision allowing aid for civilian protection.

U.S. Secretary of State John Kerry said the aid would help fighters in their effort to topple Syrian President Bashar al-Assad. The conflict has claimed more than 60,000 lives, laid waste to large portions of the country and created an enormous humanitarian crisis as refugees flee the fighting.

The fighting also threatens to widen into a regional crisis and has raised concerns that Hezbollah, Iran or others could gain control in Damascus after al-Assad's government falls.

"The United States' decision to take further steps now is the result of the continued brutality of a superior armed force propped up by foreign fighters from Iran and Hezbollah, all of which threatens to destroy Syria," Kerry said after meeting opposition leaders in Rome.

He did not say how much aid, but did announce that the United States would separately give $60 million to local groups working with the opposition Syrian National Council to provide political administration and basic services in rebel-controlled areas of Syria.

That's on top of $50 million in similar aid the United States has previously pledged to the council, as well as $385 million in humanitarian assistance, Kerry said.

"This funding will allow the opposition to reach out and help the local councils to be able to rebuild in their liberated areas of Syria so that they can provide basic services to people who so often lack access today to medical care, to food, to sanitation," he said.

Islamist Influence

The aid represents, in part, an effort to hem in radical Islamist groups vying for influence in Syria after the fall of al-Assad, a senior State Department official told CNN.

"If the Syrian opposition coalition can't touch, improve and heal the lives of Syrians in those places that have been freed, then extremists will step in and do it," the official said.

Sheikh Ahmed Moaz al-Khatib, president of the Syrian National Council, said concerns about Islamist influence were overstated.

"We stand against every radical belief that aims to target Syria's diverse social and religious fabric," he said.

U.S. officials hope the aid will help the coalition show what it can do and encourage al-Assad supporters to "peel away from him" and help end the fighting, the official said.

The opposition council will decide where the money goes, Kerry said.

But the United States will send technical advisers through its partners to the group's Cairo headquarters to ensure the aid is used properly, the senior State Department official said.

Additional aid possible

The European Council carved out an exception in its sanctions against Syria on Thursday to allow for the transfer of nonlethal equipment and technical assistance for civilian protection only.

The council did not specify what kind of equipment could be involved.

British Foreign Secretary William Hague said Friday on Twitter that his country would pledge new aid because "we cannot stand still while the crisis worsens and thousands of lives are at stake."